NAME¶
check_postgres - a Postgres monitoring script for Nagios, MRTG, Cacti, and
  others
This documents describes check_postgres version 2.19.0
SYNOPSIS¶
  ## Create all symlinks
  check_postgres --symlinks
  ## Check connection to Postgres database 'pluto':
  check_postgres --action=connection --db=pluto
  ## Same things, but using the symlink
  check_postgres_connection --db=pluto
  ## Warn if > 100 locks, critical if > 200, or > 20 exclusive
  check_postgres_locks --warning=100 --critical="total=200;exclusive=20"
  ## Show the current number of idle connections on port 6543:
  check_postgres_txn_idle --port=6543 --output=simple
  ## There are many other actions and options, please keep reading.
  The latest news and documentation can always be found at:
  http://bucardo.org/check_postgres/
DESCRIPTION¶
check_postgres is a Perl script that runs many different tests against one or
  more Postgres databases. It uses the psql program to gather the information,
  and outputs the results in one of three formats: Nagios, MRTG, or simple.
Output Modes¶
The output can be changed by use of the "--output" option. The default
  output is nagios, although this can be changed at the top of the script if you
  wish. The current option choices are 
nagios, 
mrtg, and
  
simple. To avoid having to enter the output argument each time, the
  type of output is automatically set if no --output argument is given, and if
  the current directory has one of the output options in its name. For example,
  creating a directory named mrtg and populating it with symlinks via the
  
--symlinks argument would ensure that any actions run from that
  directory will always default to an output of "mrtg" As a shortcut
  for --output=simple, you can enter --simple, which also overrides the
  directory naming trick.
Nagios output
The default output format is for Nagios, which is a single line of information,
  along with four specific exit codes:
  - 0 (OK)
  - 1 (WARNING)
  - 2 (CRITICAL)
  - 3 (UNKNOWN)
The output line is one of the words above, a colon, and then a short description
  of what was measured. Additional statistics information, as well as the total
  time the command took, can be output as well: see the documentation on the
  arguments 
--showperf, 
--perflimit, and 
--showtime.
MRTG output
The MRTG output is four lines, with the first line always giving a single number
  of importance. When possible, this number represents an actual value such as a
  number of bytes, but it may also be a 1 or a 0 for actions that only return
  "true" or "false", such as check_postgres_version. The
  second line is an additional stat and is only used for some actions. The third
  line indicates an "uptime" and is not used. The fourth line is a
  description and usually indicates the name of the database the stat from the
  first line was pulled from, but may be different depending on the action.
Some actions accept an optional 
--mrtg argument to further control the
  output.
See the documentation on each action for details on the exact MRTG output for
  each one.
Simple output
The simple output is simply a truncated version of the MRTG one, and simply
  returns the first number and nothing else. This is very useful when you just
  want to check the state of something, regardless of any threshold. You can
  transform the numeric output by appending KB, MB, GB, TB, or EB to the output
  argument, for example:
  --output=simple,MB
Cacti output
The Cacti output consists of one or more items on the same line, with a simple
  name, a colon, and then a number. At the moment, the only action with explicit
  Cacti output is 'dbstats', and using the --output option is not needed in this
  case, as Cacti is the only output for this action. For many other actions,
  using --simple is enough to make Cacti happy.
DATABASE CONNECTION OPTIONS¶
All actions accept a common set of database options.
  - -H NAME or --host=NAME
- Connect to the host indicated by NAME. Can be a
      comma-separated list of names. Multiple host arguments are allowed. If no
      host is given, defaults to the "PGHOST" environment variable or
      no host at all (which indicates using a local Unix socket). You may also
      use "--dbhost".
  - -p PORT or --port=PORT
- Connects using the specified PORT number. Can be a
      comma-separated list of port numbers, and multiple port arguments are
      allowed. If no port number is given, defaults to the "PGPORT"
      environment variable. If that is not set, it defaults to 5432. You may
      also use "--dbport"
  - -db NAME or --dbname=NAME
- Specifies which database to connect to. Can be a
      comma-separated list of names, and multiple dbname arguments are allowed.
      If no dbname option is provided, defaults to the "PGDATABASE"
      environment variable. If that is not set, it defaults to 'postgres' if
      psql is version 8 or greater, and 'template1' otherwise.
  - -u USERNAME or --dbuser=USERNAME
- The name of the database user to connect as. Can be a
      comma-separated list of usernames, and multiple dbuser arguments are
      allowed. If this is not provided, it defaults to the "PGUSER"
      environment variable, otherwise it defaults to 'postgres'.
  - --dbpass=PASSWORD
- Provides the password to connect to the database with. Use
      of this option is highly discouraged. Instead, one should use a .pgpass or
      pg_service.conf file.
  - --dbservice=NAME
- The name of a service inside of the pg_service.conf file.
      This file is in your home directory by default and contains a simple list
      of connection options. You can also pass additional information when using
      this option such as --dbservice="maindatabase
    sslmode=require"
The database connection options can be grouped: 
--host=a,b --host=c
  --port=1234 --port=3344 would connect to a-1234, b-1234, and c-3344. Note
  that once set, an option carries over until it is changed again.
Examples:
  --host=a,b --port=5433 --db=c
  Connects twice to port 5433, using database c, to hosts a and b: a-5433-c b-5433-c
  --host=a,b --port=5433 --db=c,d
  Connects four times: a-5433-c a-5433-d b-5433-c b-5433-d
  --host=a,b --host=foo --port=1234 --port=5433 --db=e,f
  Connects six times: a-1234-e a-1234-f b-1234-e b-1234-f foo-5433-e foo-5433-f
  --host=a,b --host=x --port=5432,5433 --dbuser=alice --dbuser=bob -db=baz
  Connects three times: a-5432-alice-baz b-5433-alice-baz x-5433-bob-baz
  --dbservice="foo" --port=5433
  Connects using the named service 'foo' in the pg_service.conf file, but overrides the port
OTHER OPTIONS¶
Other options include:
  - --action=NAME
- States what action we are running. Required unless using a
      symlinked file, in which case the name of the file is used to figure out
      the action.
  - --warning=VAL or -w VAL
- Sets the threshold at which a warning alert is fired. The
      valid options for this option depends on the action used.
  - --critical=VAL or -c VAL
- Sets the threshold at which a critical alert is fired. The
      valid options for this option depends on the action used.
  - -t VAL or --timeout=VAL
- Sets the timeout in seconds after which the script will
      abort whatever it is doing and return an UNKNOWN status. The timeout is
      per Postgres cluster, not for the entire script. The default value is 10;
      the units are always in seconds.
  - --assume-standby-mode
- If specified, first the check if server in standby mode
      will be performed (--datadir is required), if so, all checks that require
      SQL queries will be ignored and "Server in standby mode" with OK
      status will be returned instead.
      Example:      postgres@db$./check_postgres --action=version --warning=8.1 --datadir /var/lib/postgresql/8.3/main/ --assume-standby-mode
    POSTGRES_VERSION OK:  Server in standby mode | time=0.00
    
  - --assume-prod
- If specified, check if server in production mode is
      performed (--datadir is required). The option is only relevant for
      ("symlink: check_postgres_checkpoint").
      Example:      postgres@db$./check_postgres --action=checkpoint --datadir /var/lib/postgresql/8.3/main/ --assume-prod
    POSTGRES_CHECKPOINT OK: Last checkpoint was 72 seconds ago | age=72;;300 mode=MASTER
    
  - -h or --help
- Displays a help screen with a summary of all actions and
      options.
  - --man
- Displays the entire manual.
  - -V or --version
- Shows the current version.
  - -v or --verbose
- Set the verbosity level. Can call more than once to boost
      the level. Setting it to three or higher (in other words, issuing "-v
      -v -v") turns on debugging information for this program which is sent
      to stderr.
  - --showperf=VAL
- Determines if we output additional performance data in
      standard Nagios format (at end of string, after a pipe symbol, using
      name=value). VAL should be 0 or 1. The default is 1. Only takes effect if
      using Nagios output mode.
  - --perflimit=i
- Sets a limit as to how many items of interest are reported
      back when using the showperf option. This only has an effect for
      actions that return a large number of items, such as table_size.
      The default is 0, or no limit. Be careful when using this with the
      --include or --exclude options, as those restrictions are
      done after the query has been run, and thus your limit may not
      include the items you want. Only takes effect if using Nagios output
    mode.
  - --showtime=VAL
- Determines if the time taken to run each query is shown in
      the output. VAL should be 0 or 1. The default is 1. No effect unless
      showperf is on. Only takes effect if using Nagios output mode.
  - --test
- Enables test mode. See the "TEST MODE" section
      below.
  - --PSQL=PATH
- Tells the script where to find the psql program. Useful if
      you have more than one version of the psql executable on your system, or
      if there is no psql program in your path. Note that this option is in all
      uppercase. By default, this option is not allowed. To enable it,
      you must change the $NO_PSQL_OPTION near the top of the script to 0. Avoid
      using this option if you can, and instead hard-code your psql location
      into the $PSQL variable, also near the top of the script.
  - --symlinks
- Creates symlinks to the main program for each action.
  - --output=VAL
- Determines the format of the output, for use in various
      programs. The default is 'nagios'. Available options are 'nagios', 'mrtg',
      'simple' and 'cacti'.
  - --mrtg=VAL
- Used only for the MRTG or simple output, for a few specific
      actions.
  - --debugoutput=VAL
- Outputs the exact string returned by psql, for use in
      debugging. The value is one or more letters, which determine if the output
      is displayed or not, where 'a' = all, 'c' = critical, 'w' = warning, 'o' =
      ok, and 'u' = unknown. Letters can be combined.
  - --get_method=VAL
- Allows specification of the method used to fetch
      information for the "new_version_cp",
      "new_version_pg", "new_version_bc",
      "new_version_box", and "new_version_tnm" checks. The
      following programs are tried, in order, to grab the information from the
      web: GET, wget, fetch, curl, lynx, links. To force the use of just one
      (and thus remove the overhead of trying all the others until one of those
      works), enter one of the names as the argument to get_method. For example,
      a BSD box might enter the following line in their
      ".check_postgresrc" file:
        get_method=fetch
    
  - --language=VAL
- Set the language to use for all output messages. Normally,
      this is detected by examining the environment variables LC_ALL,
      LC_MESSAGES, and LANG, but setting this option will override any such
      detection.
ACTIONS¶
The script runs one or more actions. This can either be done with the --action
  flag, or by using a symlink to the main file that contains the name of the
  action inside of it. For example, to run the action "timesync", you
  may either issue:
  check_postgres --action=timesync
or use a program named:
  check_postgres_timesync
All the symlinks are created for you in the current directory if use the option
  --symlinks
  perl check_postgres --symlinks
If the file name already exists, it will not be overwritten. If the file exists
  and is a symlink, you can force it to overwrite by using
  "--action=build_symlinks_force"
Most actions take a 
--warning and a 
--critical option, indicating
  at what point we change from OK to WARNING, and what point we go to CRITICAL.
  Note that because criticals are always checked first, setting the warning
  equal to the critical is an effective way to turn warnings off and always give
  a critical.
The current supported actions are:
archive_ready¶
("symlink: check_postgres_archive_ready") Checks how many WAL files
  with extension 
.ready exist in the 
pg_xlog/archive_status
  directory, which is found off of your 
data_directory. This action must
  be run as a superuser, in order to access the contents of the
  
pg_xlog/archive_status directory. The minimum version to use this
  action is Postgres 8.1. The 
--warning and 
--critical options are
  simply the number of 
.ready files in the 
pg_xlog/archive_status
  directory. Usually, these values should be low, turning on the archive
  mechanism, we usually want it to archive WAL files as fast as possible.
If the archive command fail, number of WAL in your 
pg_xlog directory will
  grow until exhausting all the disk space and force PostgreSQL to stop
  immediately.
Example 1: Check that the number of ready WAL files is 10 or less on host
  "pluto"
  check_postgres_archive_ready --host=pluto --critical=10
For MRTG output, reports the number of ready WAL files on line 1.
autovac_freeze¶
("symlink: check_postgres_autovac_freeze") Checks how close each
  database is to the Postgres 
autovacuum_freeze_max_age setting. This
  action will only work for databases version 8.2 or higher. The
  
--warning and 
--critical options should be expressed as
  percentages. The 'age' of the transactions in each database is compared to the
  autovacuum_freeze_max_age setting (200 million by default) to generate a
  rounded percentage. The default values are 
90% for the warning and
  
95% for the critical. Databases can be filtered by use of the
  
--include and 
--exclude options. See the "BASIC
  FILTERING" section for more details.
Example 1: Give a warning when any databases on port 5432 are above 97%
  check_postgres_autovac_freeze --port=5432 --warning="97%"
For MRTG output, the highest overall percentage is reported on the first line,
  and the highest age is reported on the second line. All databases which have
  the percentage from the first line are reported on the fourth line, separated
  by a pipe symbol.
backends¶
("symlink: check_postgres_backends") Checks the current number of
  connections for one or more databases, and optionally compares it to the
  maximum allowed, which is determined by the Postgres configuration variable
  
max_connections. The 
--warning and 
--critical options can
  take one of three forms. First, a simple number can be given, which represents
  the number of connections at which the alert will be given. This choice does
  not use the 
max_connections setting. Second, the percentage of
  available connections can be given. Third, a negative number can be given
  which represents the number of connections left until 
max_connections
  is reached. The default values for 
--warning and 
--critical are
  '90%' and '95%'. You can also filter the databases by use of the
  
--include and 
--exclude options. See the "BASIC
  FILTERING" section for more details.
To view only non-idle processes, you can use the 
--noidle argument. Note
  that the user you are connecting as must be a superuser for this to work
  properly.
Example 1: Give a warning when the number of connections on host quirm reaches
  120, and a critical if it reaches 150.
  check_postgres_backends --host=quirm --warning=120 --critical=150
Example 2: Give a critical when we reach 75% of our max_connections setting on
  hosts lancre or lancre2.
  check_postgres_backends --warning='75%' --critical='75%' --host=lancre,lancre2
Example 3: Give a warning when there are only 10 more connection slots left on
  host plasmid, and a critical when we have only 5 left.
  check_postgres_backends --warning=-10 --critical=-5 --host=plasmid
Example 4: Check all databases except those with "test" in their name,
  but allow ones that are named "pg_greatest". Connect as port 5432 on
  the first two hosts, and as port 5433 on the third one. We want to always
  throw a critical when we reach 30 or more connections.
 check_postgres_backends --dbhost=hong,kong --dbhost=fooey --dbport=5432 --dbport=5433 --warning=30 --critical=30 --exclude="~test" --include="pg_greatest,~prod"
For MRTG output, the number of connections is reported on the first line, and
  the fourth line gives the name of the database, plus the current
  maximum_connections. If more than one database has been queried, the one with
  the highest number of connections is output.
bloat¶
("symlink: check_postgres_bloat") Checks the amount of bloat in tables
  and indexes. (Bloat is generally the amount of dead unused space taken up in a
  table or index. This space is usually reclaimed by use of the VACUUM command.)
  This action requires that stats collection be enabled on the target databases,
  and requires that ANALYZE is run frequently. The 
--include and
  
--exclude options can be used to filter out which tables to look at.
  See the "BASIC FILTERING" section for more details.
The 
--warning and 
--critical options can be specified as sizes,
  percents, or both. Valid size units are bytes, kilobytes, megabytes,
  gigabytes, terabytes, exabytes, petabytes, and zettabytes. You can abbreviate
  all of those with the first letter. Items without units are assumed to be
  'bytes'. The default values are '1 GB' and '5 GB'. The value represents the
  number of "wasted bytes", or the difference between what is actually
  used by the table and index, and what we compute that it should be.
Note that this action has two hard-coded values to avoid false alarms on smaller
  relations. Tables must have at least 10 pages, and indexes at least 15, before
  they can be considered by this test. If you really want to adjust these
  values, you can look for the variables 
$MINPAGES and
  
 $MINIPAGES at the top of the "check_bloat"
  subroutine. These values are ignored if either 
--exclude or
  
--include is used.
Only the top 10 most bloated relations are shown. You can change this number by
  using the 
--perflimit option to set your own limit.
The schema named 'information_schema' is excluded from this test, as the only
  tables it contains are small and do not change.
Please note that the values computed by this action are not precise, and should
  be used as a guideline only. Great effort was made to estimate the correct
  size of a table, but in the end it is only an estimate. The correct index size
  is even more of a guess than the correct table size, but both should give a
  rough idea of how bloated things are.
Example 1: Warn if any table on port 5432 is over 100 MB bloated, and critical
  if over 200 MB
  check_postgres_bloat --port=5432 --warning='100 M' --critical='200 M'
Example 2: Give a critical if table 'orders' on host 'sami' has more than 10
  megs of bloat
  check_postgres_bloat --host=sami --include=orders --critical='10 MB'
Example 3: Give a critical if table 'q4' on database 'sales' is over 50% bloated
  check_postgres_bloat --db=sales --include=q4 --critical='50%'
Example 4: Give a critical any table is over 20% bloated 
and has over 150
  MB of bloat:
  check_postgres_bloat --port=5432 --critical='20% and 150 M'
Example 5: Give a critical any table is over 40% bloated 
or has over 500
  MB of bloat:
  check_postgres_bloat --port=5432 --warning='500 M or 40%'
For MRTG output, the first line gives the highest number of wasted bytes for the
  tables, and the second line gives the highest number of wasted bytes for the
  indexes. The fourth line gives the database name, table name, and index name
  information. If you want to output the bloat ratio instead (how many times
  larger the relation is compared to how large it should be), just pass in
  "--mrtg=ratio".
checkpoint¶
("symlink: check_postgres_checkpoint") Determines how long since the
  last checkpoint has been run. This must run on the same server as the database
  that is being checked (e.g. the -h flag will not work). This check is meant to
  run on a "warm standby" server that is actively processing shipped
  WAL files, and is meant to check that your warm standby is truly 'warm'. The
  data directory must be set, either by the environment variable
  "PGDATA", or passing the "--datadir" argument. It returns
  the number of seconds since the last checkpoint was run, as determined by
  parsing the call to "pg_controldata". Because of this, the
  pg_controldata executable must be available in the current path.
  Alternatively, you can set the environment variable "PGCONTROLDATA"
  to the exact location of the pg_controldata executable, or you can specify
  "PGBINDIR" as the directory that it lives in. It is also possible to
  use the special options 
--assume-prod or 
--assume-standby-mode,
  if the mode found is not the one expected, a CRITICAL is emitted.
At least one warning or critical argument must be set.
This action requires the Date::Parse module.
For MRTG or simple output, returns the number of seconds.
cluster_id¶
("symlink: check_postgres_cluster-id") Checks that the Database System
  Identifier provided by pg_controldata is the same as last time you checked.
  This must run on the same server as the database that is being checked (e.g.
  the -h flag will not work). Either the 
--warning or the
  
--critical option should be given, but not both. The value of each one
  is the cluster identifier, an integer value. You can run with the special
  "--critical=0" option to find out an existing cluster identifier.
Example 1: Find the initial identifier
  check_postgres_cluster_id --critical=0 --datadir=/var//lib/postgresql/9.0/main
Example 2: Make sure the cluster is the same and warn if not, using the result
  from above.
  check_postgres_cluster_id  --critical=5633695740047915135
For MRTG output, returns a 1 or 0 indicating success of failure of the
  identifier to match. A identifier must be provided as the "--mrtg"
  argument. The fourth line always gives the current identifier.
commitratio¶
("symlink: check_postgres_commitratio") Checks the commit ratio of all
  databases and complains when they are too low. There is no need to run this
  command more than once per database cluster. Databases can be filtered with
  the 
--include and 
--exclude options. See the "BASIC
  FILTERING" section for more details. They can also be filtered by the
  owner of the database with the 
--includeuser and 
--excludeuser
  options. See the "USER NAME FILTERING" section for more details.
The warning and critical options should be specified as percentages. There are
  not defaults for this action: the warning and critical must be specified. The
  warning value cannot be greater than the critical value. The output returns
  all databases sorted by commitratio, smallest first.
Example: Warn if any database on host flagg is less than 90% in commitratio, and
  critical if less then 80%.
  check_postgres_database_commitratio --host=flagg --warning='90%' --critical='80%'
For MRTG output, returns the percentage of the database with the smallest
  commitratio on the first line, and the name of the database on the fourth
  line.
connection¶
("symlink: check_postgres_connection") Simply connects, issues a
  'SELECT 
version()', and leaves. Takes no 
--warning or
  
--critical options.
For MRTG output, simply outputs a 1 (good connection) or a 0 (bad connection) on
  the first line.
custom_query¶
("symlink: check_postgres_custom_query") Runs a custom query of your
  choosing, and parses the results. The query itself is passed in through the
  "query" argument, and should be kept as simple as possible. If at
  all possible, wrap it in a view or a function to keep things easier to manage.
  The query should return one or two columns. It is required that one of the
  columns be named "result" and is the item that will be checked
  against your warning and critical values. The second column is for the
  performance data and any name can be used: this will be the 'value' inside the
  performance data section.
At least one warning or critical argument must be specified. What these are set
  to depends on the type of query you are running. There are four types of
  custom_queries that can be run, specified by the "valtype" argument.
  If none is specified, this action defaults to 'integer'. The four types are:
integer: Does a simple integer comparison. The first column should be a
  simple integer, and the warning and critical values should be the same.
string: The warning and critical are strings, and are triggered only if
  the value in the first column matches it exactly. This is case-sensitive.
time: The warning and the critical are times, and can have units of
  seconds, minutes, hours, or days. Each may be written singular or abbreviated
  to just the first letter. If no units are given, seconds are assumed. The
  first column should be an integer representing the number of seconds to check.
size: The warning and the critical are sizes, and can have units of
  bytes, kilobytes, megabytes, gigabytes, terabytes, or exabytes. Each may be
  abbreviated to the first letter. If no units are given, bytes are assumed. The
  first column should be an integer representing the number of bytes to check.
Normally, an alert is triggered if the values returned are 
greater than
  or equal to the critical or warning value. However, an option of
  
--reverse will trigger the alert if the returned value is 
lower
  than or equal to the critical or warning value.
Example 1: Warn if any relation over 100 pages is named "rad", put the
  number of pages inside the performance data section.
  check_postgres_custom_query --valtype=string -w "rad" --query=
    "SELECT relname AS result, relpages AS pages FROM pg_class WHERE relpages > 100"
Example 2: Give a critical if the "foobar" function returns a number
  over 5MB:
  check_postgres_custom_query --critical='5MB'--valtype=size --query="SELECT foobar() AS result"
Example 2: Warn if the function "snazzo" returns less than 42:
  check_postgres_custom_query --critical=42 --query="SELECT snazzo() AS result" --reverse
If you come up with a useful custom_query, consider sending in a patch to this
  program to make it into a standard action that other people can use.
This action does not support MRTG or simple output yet.
database_size¶
("symlink: check_postgres_database_size") Checks the size of all
  databases and complains when they are too big. There is no need to run this
  command more than once per database cluster. Databases can be filtered with
  the 
--include and 
--exclude options. See the "BASIC
  FILTERING" section for more details. They can also be filtered by the
  owner of the database with the 
--includeuser and 
--excludeuser
  options. See the "USER NAME FILTERING" section for more details.
The warning and critical options can be specified as bytes, kilobytes,
  megabytes, gigabytes, terabytes, or exabytes. Each may be abbreviated to the
  first letter as well. If no unit is given, the units are assumed to be bytes.
  There are not defaults for this action: the warning and critical must be
  specified. The warning value cannot be greater than the critical value. The
  output returns all databases sorted by size largest first, showing both raw
  bytes and a "pretty" version of the size.
Example 1: Warn if any database on host flagg is over 1 TB in size, and critical
  if over 1.1 TB.
  check_postgres_database_size --host=flagg --warning='1 TB' --critical='1.1 t'
Example 2: Give a critical if the database template1 on port 5432 is over 10 MB.
  check_postgres_database_size --port=5432 --include=template1 --warning='10MB' --critical='10MB'
Example 3: Give a warning if any database on host 'tardis' owned by the user
  'tom' is over 5 GB
  check_postgres_database_size --host=tardis --includeuser=tom --warning='5 GB' --critical='10 GB'
For MRTG output, returns the size in bytes of the largest database on the first
  line, and the name of the database on the fourth line.
dbstats¶
("symlink: check_postgres_dbstats") Reports information from the
  pg_stat_database view, and outputs it in a Cacti-friendly manner. No other
  output is supported, as the output is informational and does not lend itself
  to alerts, such as used with Nagios. If no options are given, all databases
  are returned, one per line. You can include a specific database by use of the
  "--include" option, or you can use the "--dbname" option.
Eleven items are returned on each line, in the format name:value, separated by a
  single space. The items are:
  - backends
- The number of currently running backends for this
    database.
  - commits
- The total number of commits for this database since it was
      created or reset.
  - rollbacks
- The total number of rollbacks for this database since it
      was created or reset.
  - read
- The total number of disk blocks read.
  - hit
- The total number of buffer hits.
  - ret
- The total number of rows returned.
  - fetch
- The total number of rows fetched.
  - ins
- The total number of rows inserted.
  - upd
- The total number of rows updated.
  - del
- The total number of rows deleted.
  - dbname
- The name of the database.
Note that ret, fetch, ins, upd, and del items will always be 0 if Postgres is
  version 8.2 or lower, as those stats were not available in those versions.
If the dbname argument is given, seven additional items are returned:
  - idxscan
- Total number of user index scans.
  - idxtupread
- Total number of user index entries returned.
  - idxtupfetch
- Total number of rows fetched by simple user index
    scans.
  - idxblksread
- Total number of disk blocks read for all user indexes.
  - idxblkshit
- Total number of buffer hits for all user indexes.
  - seqscan
- Total number of sequential scans against all user
    tables.
  - seqtupread
- Total number of tuples returned from all user tables.
Example 1: Grab the stats for a database named "products" on host
  "willow":
  check_postgres_dbstats --dbhost willow --dbname products
The output returned will be like this (all on one line, not wrapped):
    backends:82 commits:58374408 rollbacks:1651 read:268435543 hit:2920381758 idxscan:310931294 idxtupread:2777040927
    idxtupfetch:1840241349 idxblksread:62860110 idxblkshit:1107812216 seqscan:5085305 seqtupread:5370500520
    ret:0 fetch:0 ins:0 upd:0 del:0 dbname:willow
disabled_triggers¶
("symlink: check_postgres_disabled_triggers") Checks on the number of
  disabled triggers inside the database. The 
--warning and
  
--critical options are the number of such triggers found, and both
  default to "1", as in normal usage having disabled triggers is a
  dangerous event. If the database being checked is 8.3 or higher, the check is
  for the number of triggers that are in a 'disabled' status (as opposed to
  being 'always' or 'replica'). The output will show the name of the table and
  the name of the trigger for each disabled trigger.
Example 1: Make sure that there are no disabled triggers
  check_postgres_disabled_triggers
For MRTG output, returns the number of disabled triggers on the first line.
disk_space¶
("symlink: check_postgres_disk_space") Checks on the available
  physical disk space used by Postgres. This action requires that you have the
  executable "/bin/df" available to report on disk sizes, and it also
  needs to be run as a superuser, so it can examine the 
data_directory
  setting inside of Postgres. The 
--warning and 
--critical options
  are given in either sizes or percentages or both. If using sizes, the standard
  unit types are allowed: bytes, kilobytes, gigabytes, megabytes, gigabytes,
  terabytes, or exabytes. Each may be abbreviated to the first letter only; no
  units at all indicates 'bytes'. The default values are '90%' and '95%'.
This command checks the following things to determine all of the different
  physical disks being used by Postgres.
data_directory - The disk that the main data directory is on.
log directory - The disk that the log files are on.
WAL file directory - The disk that the write-ahead logs are on (e.g.
  symlinked pg_xlog)
tablespaces - Each tablespace that is on a separate disk.
The output shows the total size used and available on each disk, as well as the
  percentage, ordered by highest to lowest percentage used. Each item above maps
  to a file system: these can be included or excluded. See the "BASIC
  FILTERING" section for more details.
Example 1: Make sure that no file system is over 90% for the database on port
  5432.
  check_postgres_disk_space --port=5432 --warning='90%' --critical="90%'
Example 2: Check that all file systems starting with /dev/sda are smaller than
  10 GB and 11 GB (warning and critical)
  check_postgres_disk_space --port=5432 --warning='10 GB' --critical='11 GB' --include="~^/dev/sda"
Example 4: Make sure that no file system is both over 50% 
and has over 15
  GB
  check_postgres_disk_space --critical='50% and 15 GB'
Example 5: Issue a warning if any file system is either over 70% full 
or
  has more than 1T
  check_postgres_disk_space --warning='1T or 75'
For MRTG output, returns the size in bytes of the file system on the first line,
  and the name of the file system on the fourth line.
fsm_pages¶
("symlink: check_postgres_fsm_pages") Checks how close a cluster is to
  the Postgres 
max_fsm_pages setting. This action will only work for
  databases of 8.2 or higher, and it requires the contrib module
  
pg_freespacemap be installed. The 
--warning and
  
--critical options should be expressed as percentages. The number of
  used pages in the free-space-map is determined by looking in the
  pg_freespacemap_relations view, and running a formula based on the formula
  used for outputting free-space-map pageslots in the vacuum verbose command.
  The default values are 
85% for the warning and 
95% for the
  critical.
Example 1: Give a warning when our cluster has used up 76% of the free-space
  pageslots, with pg_freespacemap installed in database robert
  check_postgres_fsm_pages --dbname=robert --warning="76%"
While you need to pass in the name of the database where pg_freespacemap is
  installed, you only need to run this check once per cluster. Also, checking
  this information does require obtaining special locks on the free-space-map,
  so it is recommend you do not run this check with short intervals.
For MRTG output, returns the percent of free-space-map on the first line, and
  the number of pages currently used on the second line.
fsm_relations¶
("symlink: check_postgres_fsm_relations") Checks how close a cluster
  is to the Postgres 
max_fsm_relations setting. This action will only
  work for databases of 8.2 or higher, and it requires the contrib module
  
pg_freespacemap be installed. The 
--warning and
  
--critical options should be expressed as percentages. The number of
  used relations in the free-space-map is determined by looking in the
  pg_freespacemap_relations view. The default values are 
85% for the
  warning and 
95% for the critical.
Example 1: Give a warning when our cluster has used up 80% of the free-space
  relations, with pg_freespacemap installed in database dylan
  check_postgres_fsm_relations --dbname=dylan --warning="75%"
While you need to pass in the name of the database where pg_freespacemap is
  installed, you only need to run this check once per cluster. Also, checking
  this information does require obtaining special locks on the free-space-map,
  so it is recommend you do not run this check with short intervals.
For MRTG output, returns the percent of free-space-map on the first line, the
  number of relations currently used on the second line.
hitratio¶
("symlink: check_postgres_database_hitratio") Checks the hit ratio of
  all databases and complains when they are too low. There is no need to run
  this command more than once per database cluster. Databases can be filtered
  with the 
--include and 
--exclude options. See the "BASIC
  FILTERING" section for more details. They can also be filtered by the
  owner of the database with the 
--includeuser and 
--excludeuser
  options. See the "USER NAME FILTERING" section for more details.
The warning and critical options should be specified as percentages. There are
  not defaults for this action: the warning and critical must be specified. The
  warning value cannot be greater than the critical value. The output returns
  all databases sorted by hitratio, smallest first.
Example: Warn if any database on host flagg is less than 90% in hitratio, and
  critical if less then 80%.
  check_postgres_database_hitratio --host=flagg --warning='90%' --critical='80%'
For MRTG output, returns the percentage of the database with the smallest
  hitratio on the first line, and the name of the database on the fourth line.
hot_standby_delay¶
("symlink: check_hot_standby_delay") Checks the streaming replication
  lag by computing the delta between the xlog position of a master server and
  the one of the slaves connected to it. The slave_ server must be in
  hot_standby (e.g. read only) mode, therefore the minimum version to use this_
  action is Postgres 9.0. The 
--warning and 
--critical options are
  the delta between xlog location. These values should match the volume of
  transactions needed to have the streaming replication disconnect from the
  master because of too much lag.
You must provide information on how to reach the second database by a connection
  parameter ending in the number 2, such as "--dbport2=5543". If if it
  not given, the action fails.
index_size¶
table_size¶
relation_size¶
(symlinks: "check_postgres_index_size",
  "check_postgres_table_size", and
  "check_postgres_relation_size") The actions 
table_size and
  
index_size are simply variations of the 
relation_size action,
  which checks for a relation that has grown too big. Relations (in other words,
  tables and indexes) can be filtered with the 
--include and
  
--exclude options. See the "BASIC FILTERING" section for more
  details. Relations can also be filtered by the user that owns them, by using
  the 
--includeuser and 
--excludeuser options. See the "USER
  NAME FILTERING" section for more details.
The values for the 
--warning and 
--critical options are file
  sizes, and may have units of bytes, kilobytes, megabytes, gigabytes,
  terabytes, or exabytes. Each can be abbreviated to the first letter. If no
  units are given, bytes are assumed. There are no default values: both the
  warning and the critical option must be given. The return text shows the size
  of the largest relation found.
If the 
--showperf option is enabled, 
all of the relations with
  their sizes will be given. To prevent this, it is recommended that you set the
  
--perflimit option, which will cause the query to do a "ORDER BY
  size DESC LIMIT (perflimit)".
Example 1: Give a critical if any table is larger than 600MB on host burrick.
  check_postgres_table_size --critical='600 MB' --warning='600 MB' --host=burrick
Example 2: Warn if the table products is over 4 GB in size, and give a critical
  at 4.5 GB.
  check_postgres_table_size --host=burrick --warning='4 GB' --critical='4.5 GB' --include=products
Example 3: Warn if any index not owned by postgres goes over 500 MB.
  check_postgres_index_size --port=5432 --excludeuser=postgres -w 500MB -c 600MB
For MRTG output, returns the size in bytes of the largest relation, and the name
  of the database and relation as the fourth line.
last_analyze¶
last_vacuum¶
last_autoanalyze¶
last_autovacuum¶
(symlinks: "check_postgres_last_analyze",
  "check_postgres_last_vacuum",
  "check_postgres_last_autoanalyze", and
  "check_postgres_last_autovacuum") Checks how long it has been since
  vacuum (or analyze) was last run on each table in one or more databases. Use
  of these actions requires that the target database is version 8.3 or greater,
  or that the version is 8.2 and the configuration variable
  
stats_row_level has been enabled. Tables can be filtered with the
  
--include and 
--exclude options. See the "BASIC
  FILTERING" section for more details. Tables can also be filtered by their
  owner by use of the 
--includeuser and 
--excludeuser options. See
  the "USER NAME FILTERING" section for more details.
The units for 
--warning and 
--critical are specified as times.
  Valid units are seconds, minutes, hours, and days; all can be abbreviated to
  the first letter. If no units are given, 'seconds' are assumed. The default
  values are '1 day' and '2 days'. Please note that there are cases in which
  this field does not get automatically populated. If certain tables are giving
  you problems, make sure that they have dead rows to vacuum, or just exclude
  them from the test.
The schema named 'information_schema' is excluded from this test, as the only
  tables it contains are small and do not change.
Note that the non-'auto' versions will also check on the auto versions as well.
  In other words, using last_vacuum will report on the last vacuum, whether it
  was a normal vacuum, or one run by the autovacuum daemon.
Example 1: Warn if any table has not been vacuumed in 3 days, and give a
  critical at a week, for host wormwood
  check_postgres_last_vacuum --host=wormwood --warning='3d' --critical='7d'
Example 2: Same as above, but skip tables belonging to the users 'eve' or
  'mallory'
  check_postgres_last_vacuum --host=wormwood --warning='3d' --critical='7d' --excludeusers=eve,mallory
For MRTG output, returns (on the first line) the LEAST amount of time in seconds
  since a table was last vacuumed or analyzed. The fourth line returns the name
  of the database and name of the table.
listener¶
("symlink: check_postgres_listener") Confirm that someone is listening
  for one or more specific strings (using the LISTEN/NOTIFY system), by looking
  at the pg_listener table. Only one of warning or critical is needed. The
  format is a simple string representing the LISTEN target, or a tilde character
  followed by a string for a regular expression check. Note that this check will
  not work on versions of Postgres 9.0 or higher.
Example 1: Give a warning if nobody is listening for the string bucardo_mcp_ping
  on ports 5555 and 5556
  check_postgres_listener --port=5555,5556 --warning=bucardo_mcp_ping
Example 2: Give a critical if there are no active LISTEN requests matching
  'grimm' on database oskar
  check_postgres_listener --db oskar --critical=~grimm
For MRTG output, returns a 1 or a 0 on the first, indicating success or failure.
  The name of the notice must be provided via the 
--mrtg option.
locks¶
("symlink: check_postgres_locks") Check the total number of locks on
  one or more databases. There is no need to run this more than once per
  database cluster. Databases can be filtered with the 
--include and
  
--exclude options. See the "BASIC FILTERING" section for more
  details.
The 
--warning and 
--critical options can be specified as simple
  numbers, which represent the total number of locks, or they can be broken down
  by type of lock. Valid lock names are 'total', 'waiting', or the name of a
  lock type used by Postgres. These names are case-insensitive and do not need
  the "lock" part on the end, so 
exclusive will match
  'ExclusiveLock'. The format is name=number, with different items separated by
  semicolons.
Example 1: Warn if the number of locks is 100 or more, and critical if 200 or
  more, on host garrett
  check_postgres_locks --host=garrett --warning=100 --critical=200
Example 2: On the host artemus, warn if 200 or more locks exist, and give a
  critical if over 250 total locks exist, or if over 20 exclusive locks exist,
  or if over 5 connections are waiting for a lock.
  check_postgres_locks --host=artemus --warning=200 --critical="total=250;waiting=5;exclusive=20"
For MRTG output, returns the number of locks on the first line, and the name of
  the database on the fourth line.
logfile¶
("symlink: check_postgres_logfile") Ensures that the logfile is in the
  expected location and is being logged to. This action issues a command that
  throws an error on each database it is checking, and ensures that the message
  shows up in the logs. It scans the various log_* settings inside of Postgres
  to figure out where the logs should be. If you are using syslog, it does a
  rough (but not foolproof) scan of 
/etc/syslog.conf. Alternatively, you
  can provide the name of the logfile with the 
--logfile option. This is
  especially useful if the logs have a custom rotation scheme driven be an
  external program. The 
--logfile option supports the following escape
  characters: "%Y %m %d %H", which represent the current year, month,
  date, and hour respectively. An error is always reported as critical unless
  the warning option has been passed in as a non-zero value. Other than that
  specific usage, the "--warning" and "--critical" options
  should 
not be used.
Example 1: On port 5432, ensure the logfile is being written to the file
  /home/greg/pg8.2.log
  check_postgres_logfile --port=5432 --logfile=/home/greg/pg8.2.log
Example 2: Same as above, but raise a warning, not a critical
  check_postgres_logfile --port=5432 --logfile=/home/greg/pg8.2.log -w 1
For MRTG output, returns a 1 or 0 on the first line, indicating success or
  failure. In case of a failure, the fourth line will provide more detail on the
  failure encountered.
new_version_bc¶
("symlink: check_postgres_new_version_bc") Checks if a newer version
  of the Bucardo program is available. The current version is obtained by
  running "bucardo_ctl --version". If a major upgrade is available, a
  warning is returned. If a revision upgrade is available, a critical is
  returned. (Bucardo is a master to slave, and master to master replication
  system for Postgres: see 
http://bucardo.org for more information). See also
  the information on the "--get_method" option.
new_version_box¶
("symlink: check_postgres_new_version_box") Checks if a newer version
  of the boxinfo program is available. The current version is obtained by
  running "boxinfo.pl --version". If a major upgrade is available, a
  warning is returned. If a revision upgrade is available, a critical is
  returned. (boxinfo is a program for grabbing important information from a
  server and putting it into a HTML format: see 
http://bucardo.org/wiki/boxinfo
  for more information). See also the information on the
  "--get_method" option.
new_version_cp¶
("symlink: check_postgres_new_version_cp") Checks if a newer version
  of this program (check_postgres) is available, by grabbing the version from a
  small text file on the main page of the home page for the project. Returns a
  warning if the returned version does not match the one you are running.
  Recommended interval to check is once a day. See also the information on the
  "--get_method" option.
new_version_pg¶
("symlink: check_postgres_new_version_pg") Checks if a newer revision
  of Postgres exists for each database connected to. Note that this only checks
  for revision, e.g. going from 8.3.6 to 8.3.7. Revisions are always 100% binary
  compatible and involve no dump and restore to upgrade. Revisions are made to
  address bugs, so upgrading as soon as possible is always recommended. Returns
  a warning if you do not have the latest revision. It is recommended this check
  is run at least once a day. See also the information on the
  "--get_method" option.
new_version_tnm¶
("symlink: check_postgres_new_version_tnm") Checks if a newer version
  of the tail_n_mail program is available. The current version is obtained by
  running "tail_n_mail --version". If a major upgrade is available, a
  warning is returned. If a revision upgrade is available, a critical is
  returned. (tail_n_mail is a log monitoring tool that can send mail when
  interesting events appear in your Postgres logs. See:
  
http://bucardo.org/wiki/Tail_n_mail for more information). See also the
  information on the "--get_method" option.
pgb_pool_cl_active¶
pgb_pool_cl_waiting¶
pgb_pool_sv_active¶
pgb_pool_sv_idle¶
pgb_pool_sv_used¶
pgb_pool_sv_tested¶
pgb_pool_sv_login¶
pgb_pool_maxwait¶
(symlinks: "check_postgres_pgb_pool_cl_active",
  "check_postgres_pgb_pool_cl_waiting",
  "check_postgres_pgb_pool_sv_active",
  "check_postgres_pgb_pool_sv_idle",
  "check_postgres_pgb_pool_sv_used",
  "check_postgres_pgb_pool_sv_tested",
  "check_postgres_pgb_pool_sv_login", and
  "check_postgres_pgb_pool_maxwait")
Examines pgbouncer's pool statistics. Each pool has a set of "client"
  connections, referring to connections from external clients, and
  "server" connections, referring to connections to PostgreSQL itself.
  The related check_postgres actions are prefixed by "cl_" and
  "sv_", respectively. Active client connections are those connections
  currently linked with an active server connection. Client connections may also
  be "waiting", meaning they have not yet been allocated a server
  connection. Server connections are "active" (linked to a client),
  "idle" (standing by for a client connection to link with),
  "used" (just unlinked from a client, and not yet returned to the
  idle pool), "tested" (currently being tested) and "login"
  (in the process of logging in). The maxwait value shows how long in seconds
  the oldest waiting client connection has been waiting.
pgbouncer_backends¶
("symlink: check_postgres_pgbouncer_backends") Checks the current
  number of connections for one or more databases through pgbouncer, and
  optionally compares it to the maximum allowed, which is determined by the
  pgbouncer configuration variable 
max_client_conn. The 
--warning
  and 
--critical options can take one of three forms. First, a simple
  number can be given, which represents the number of connections at which the
  alert will be given. This choice does not use the 
max_connections
  setting. Second, the percentage of available connections can be given. Third,
  a negative number can be given which represents the number of connections left
  until 
max_connections is reached. The default values for
  
--warning and 
--critical are '90%' and '95%'. You can also
  filter the databases by use of the 
--include and 
--exclude
  options. See the "BASIC FILTERING" section for more details.
To view only non-idle processes, you can use the 
--noidle argument. Note
  that the user you are connecting as must be a superuser for this to work
  properly.
Example 1: Give a warning when the number of connections on host quirm reaches
  120, and a critical if it reaches 150.
  check_postgres_pgbouncer_backends --host=quirm --warning=120 --critical=150 -p 6432 -u pgbouncer
Example 2: Give a critical when we reach 75% of our max_connections setting on
  hosts lancre or lancre2.
  check_postgres_pgbouncer_backends --warning='75%' --critical='75%' --host=lancre,lancre2 -p 6432 -u pgbouncer
Example 3: Give a warning when there are only 10 more connection slots left on
  host plasmid, and a critical when we have only 5 left.
  check_postgres_pgbouncer_backends --warning=-10 --critical=-5 --host=plasmid -p 6432 -u pgbouncer
For MRTG output, the number of connections is reported on the first line, and
  the fourth line gives the name of the database, plus the current
  max_client_conn. If more than one database has been queried, the one with the
  highest number of connections is output.
pgbouncer_checksum¶
("symlink: check_postgres_pgbouncer_checksum") Checks that all the
  pgBouncer settings are the same as last time you checked. This is done by
  generating a checksum of a sorted list of setting names and their values. Note
  that you shouldn't specify the database name, it will automatically default to
  pgbouncer. Either the 
--warning or the 
--critical option should
  be given, but not both. The value of each one is the checksum, a 32-character
  hexadecimal value. You can run with the special "--critical=0"
  option to find out an existing checksum.
This action requires the Digest::MD5 module.
Example 1: Find the initial checksum for pgbouncer configuration on port 6432
  using the default user (usually postgres)
  check_postgres_pgbouncer_checksum --port=6432 --critical=0
Example 2: Make sure no settings have changed and warn if so, using the checksum
  from above.
  check_postgres_pgbouncer_checksum --port=6432 --warning=cd2f3b5e129dc2b4f5c0f6d8d2e64231
For MRTG output, returns a 1 or 0 indicating success of failure of the checksum
  to match. A checksum must be provided as the "--mrtg" argument. The
  fourth line always gives the current checksum.
prepared_txns¶
("symlink: check_postgres_prepared_txns") Check on the age of any
  existing prepared transactions. Note that most people will NOT use prepared
  transactions, as they are part of two-part commit and complicated to maintain.
  They should also not be confused with prepared STATEMENTS, which is what most
  people think of when they hear prepare. The default value for a warning is 1
  second, to detect any use of prepared transactions, which is probably a
  mistake on most systems. Warning and critical are the number of seconds a
  prepared transaction has been open before an alert is given.
Example 1: Give a warning on detecting any prepared transactions:
  check_postgres_prepared_txns -w 0
Example 2: Give a critical if any prepared transaction has been open longer than
  10 seconds, but allow up to 360 seconds for the database 'shrike':
  check_postgres_prepared_txns --critical=10 --exclude=shrike
  check_postgres_prepared_txns --critical=360 --include=shrike
For MRTG output, returns the number of seconds the oldest transaction has been
  open as the first line, and which database is came from as the final line.
query_runtime¶
("symlink: check_postgres_query_runtime") Checks how long a specific
  query takes to run, by executing a "EXPLAIN ANALYZE" against it. The
  
--warning and 
--critical options are the maximum amount of time
  the query should take. Valid units are seconds, minutes, and hours; any can be
  abbreviated to the first letter. If no units are given, 'seconds' are assumed.
  Both the warning and the critical option must be given. The name of the view
  or function to be run must be passed in to the 
--queryname option. It
  must consist of a single word (or schema.word), with optional parens at the
  end.
Example 1: Give a critical if the function named "speedtest" fails to
  run in 10 seconds or less.
  check_postgres_query_runtime --queryname='speedtest()' --critical=10 --warning=10
For MRTG output, reports the time in seconds for the query to complete on the
  first line. The fourth line lists the database.
query_time¶
("symlink: check_postgres_query_time") Checks the length of running
  queries on one or more databases. There is no need to run this more than once
  on the same database cluster. Note that this already excludes queries that are
  "idle in transaction". Databases can be filtered by using the
  
--include and 
--exclude options. See the "BASIC
  FILTERING" section for more details. You can also filter on the user
  running the query with the 
--includeuser and 
--excludeuser
  options. See the "USER NAME FILTERING" section for more details.
The values for the 
--warning and 
--critical options are amounts of
  time, and default to '2 minutes' and '5 minutes' respectively. Valid units are
  'seconds', 'minutes', 'hours', or 'days'. Each may be written singular or
  abbreviated to just the first letter. If no units are given, the unit is
  assumed to be seconds.
This action requires Postgres 8.1 or better.
Example 1: Give a warning if any query has been running longer than 3 minutes,
  and a critical if longer than 5 minutes.
  check_postgres_query_time --port=5432 --warning='3 minutes' --critical='5 minutes'
Example 2: Using default values (2 and 5 minutes), check all databases except
  those starting with 'template'.
  check_postgres_query_time --port=5432 --exclude=~^template
Example 3: Warn if user 'don' has a query running over 20 seconds
  check_postgres_query_time --port=5432 --includeuser=don --warning=20s
For MRTG output, returns the length in seconds of the longest running query on
  the first line. The fourth line gives the name of the database.
replicate_row¶
("symlink: check_postgres_replicate_row") Checks that master-slave
  replication is working to one or more slaves. The slaves are specified the
  same as the normal databases, except with the number 2 at the end of them, so
  "--port2" instead of "--port", etc. The values or the
  
--warning and 
--critical options are units of time, and at least
  one must be provided (no defaults). Valid units are 'seconds', 'minutes',
  'hours', or 'days'. Each may be written singular or abbreviated to just the
  first letter. If no units are given, the units are assumed to be seconds.
This check updates a single row on the master, and then measures how long it
  takes to be applied to the slaves. To do this, you need to pick a table that
  is being replicated, then find a row that can be changed, and is not going to
  be changed by any other process. A specific column of this row will be changed
  from one value to another. All of this is fed to the "repinfo"
  option, and should contain the following options, separated by commas: table
  name, primary key, key id, column, first value, second value.
Example 1: Slony is replicating a table named 'orders' from host 'alpha' to host
  'beta', in the database 'sales'. The primary key of the table is named id, and
  we are going to test the row with an id of 3 (which is historical and never
  changed). There is a column named 'salesrep' that we are going to toggle from
  a value of 'slon' to 'nols' to check on the replication. We want to throw a
  warning if the replication does not happen within 10 seconds.
  check_postgres_replicate_row --host=alpha --dbname=sales --host2=beta 
  --dbname2=sales --warning=10 --repinfo=orders,id,3,salesrep,slon,nols
Example 2: Bucardo is replicating a table named 'receipt' from host 'green' to
  hosts 'red', 'blue', and 'yellow'. The database for both sides is 'public'.
  The slave databases are running on port 5455. The primary key is named
  'receipt_id', the row we want to use has a value of 9, and the column we want
  to change for the test is called 'zone'. We'll toggle between 'north' and
  'south' for the value of this column, and throw a critical if the change is
  not on all three slaves within 5 seconds.
 check_postgres_replicate_row --host=green --port2=5455 --host2=red,blue,yellow
  --critical=5 --repinfo=receipt,receipt_id,9,zone,north,south
For MRTG output, returns on the first line the time in seconds the replication
  takes to finish. The maximum time is set to 4 minutes 30 seconds: if no
  replication has taken place in that long a time, an error is thrown.
same_schema¶
("symlink: check_postgres_same_schema") Verifies that two or more
  databases are identical as far as their schema (but not the data within). This
  is particularly handy for making sure your slaves have not been modified or
  corrupted in any way when using master to slave replication. Unlike most other
  actions, this has no warning or critical criteria - the databases are either
  in sync, or are not. If they are different, a detailed list of the differences
  is presented.
You may want to exclude or filter out certain differences. The way to do this is
  to add strings to the "--filter" option. To exclude a type of
  object, use "noname", where 'name' is the type of object, for
  example, "noschema". To exclude objects of a certain type by a
  regular expression against their name, use "noname=regex". See the
  examples below for a better understanding.
The types of objects that can be filtered include:
  - user
  - schema
  - table
  - view
  - index
  - sequence
  - constraint
  - trigger
  - function
The filter option "noposition" prevents verification of the position
  of columns within a table.
The filter option "nofuncbody" prevents comparison of the bodies of
  all functions.
The filter option "noperm" prevents comparison of object permissions.
To provide the second database, just append the differences to the first one by
  a call to the appropriate connection argument. For example, to compare
  databases on hosts alpha and bravo, use "--dbhost=alpha,bravo". Also
  see the examples below.
If only a single host is given, it is assumed we are doing a
  "time-based" report. The first time this is run a snapshot of all
  the items in the database is saved to a local file. When you run it again,
  that snapshot is read in and becomes "database #2" and is compared
  to the current database.
To replace the old stored file with the new version, use the --replace argument.
To enable snapshots at various points in time, you can use the
  "--suffix" argument to make the filenames unique to each run. See
  the examples below.
Example 1: Verify that two databases on hosts star and line are the same:
  check_postgres_same_schema --dbhost=star,line
Example 2: Same as before, but exclude any triggers with "slony" in
  their name
  check_postgres_same_schema --dbhost=star,line --filter="notrigger=slony"
Example 3: Same as before, but also exclude all indexes
  check_postgres_same_schema --dbhost=star,line --filter="notrigger=slony noindexes"
Example 4: Check differences for the database "battlestar" on
  different ports
  check_postgres_same_schema --dbname=battlestar --dbport=5432,5544
Example 5: Create a daily and weekly snapshot file
  check_postgres_same_schema --dbname=cylon --suffix=daily
  check_postgres_same_schema --dbname=cylon --suffix=weekly
Example 6: Run a historical comparison, then replace the file
  check_postgres_same_schema --dbname=cylon --suffix=daily --replace
sequence¶
("symlink: check_postgres_sequence") Checks how much room is left on
  all sequences in the database. This is measured as the percent of total
  possible values that have been used for each sequence. The 
--warning
  and 
--critical options should be expressed as percentages. The default
  values are 
85% for the warning and 
95% for the critical. You may
  use --include and --exclude to control which sequences are to be checked. Note
  that this check does account for unusual 
minvalue and 
increment
  by values, but does not care if the sequence is set to cycle or not.
The output for Nagios gives the name of the sequence, the percentage used, and
  the number of 'calls' left, indicating how many more times nextval can be
  called on that sequence before running into the maximum value.
The output for MRTG returns the highest percentage across all sequences on the
  first line, and the name of each sequence with that percentage on the fourth
  line, separated by a "|" (pipe) if there are more than one sequence
  at that percentage.
Example 1: Give a warning if any sequences are approaching 95% full.
  check_postgres_sequence --dbport=5432 --warning=95%
Example 2: Check that the sequence named "orders_id_seq" is not more
  than half full.
  check_postgres_sequence --dbport=5432 --critical=50% --include=orders_id_seq
settings_checksum¶
("symlink: check_postgres_settings_checksum") Checks that all the
  Postgres settings are the same as last time you checked. This is done by
  generating a checksum of a sorted list of setting names and their values. Note
  that different users in the same database may have different checksums, due to
  ALTER USER usage, and due to the fact that superusers see more settings than
  ordinary users. Either the 
--warning or the 
--critical option
  should be given, but not both. The value of each one is the checksum, a
  32-character hexadecimal value. You can run with the special
  "--critical=0" option to find out an existing checksum.
This action requires the Digest::MD5 module.
Example 1: Find the initial checksum for the database on port 5555 using the
  default user (usually postgres)
  check_postgres_settings_checksum --port=5555 --critical=0
Example 2: Make sure no settings have changed and warn if so, using the checksum
  from above.
  check_postgres_settings_checksum --port=5555 --warning=cd2f3b5e129dc2b4f5c0f6d8d2e64231
For MRTG output, returns a 1 or 0 indicating success of failure of the checksum
  to match. A checksum must be provided as the "--mrtg" argument. The
  fourth line always gives the current checksum.
slony_status¶
("symlink: check_postgres_slony_status") Checks in the status of a
  Slony cluster by looking at the results of Slony's sl_status view. This is
  returned as the number of seconds of "lag time". The
  
--warning and 
--critical options should be expressed as times.
  The default values are 
60 seconds for the warning and 
300
  seconds for the critical.
The optional argument 
--schema indicated the schema that Slony is
  installed under. If it is not given, the schema will be determined
  automatically each time this check is run.
Example 1: Give a warning if any Slony is lagged by more than 20 seconds
  check_postgres_slony_status --warning 20
Example 2: Give a critical if Slony, installed under the schema
  "_slony", is over 10 minutes lagged
  check_postgres_slony_status --schema=_slony --critical=600
timesync¶
("symlink: check_postgres_timesync") Compares the local system time
  with the time reported by one or more databases. The 
--warning and
  
--critical options represent the number of seconds between the two
  systems before an alert is given. If neither is specified, the default values
  are used, which are '2' and '5'. The warning value cannot be greater than the
  critical value. Due to the non-exact nature of this test, values of '0' or '1'
  are not recommended.
The string returned shows the time difference as well as the time on each side
  written out.
Example 1: Check that databases on hosts ankh, morpork, and klatch are no more
  than 3 seconds off from the local time:
  check_postgres_timesync --host=ankh,morpork,klatch --critical=3
For MRTG output, returns one the first line the number of seconds difference
  between the local time and the database time. The fourth line returns the name
  of the database.
txn_idle¶
("symlink: check_postgres_txn_idle") Checks the number and duration of
  "idle in transaction" queries on one or more databases. There is no
  need to run this more than once on the same database cluster. Databases can be
  filtered by using the 
--include and 
--exclude options. See the
  "BASIC FILTERING" section below for more details.
The 
--warning and 
--critical options are given as units of time,
  signed integers, or integers for units of time, and both must be provided
  (there are no defaults). Valid units are 'seconds', 'minutes', 'hours', or
  'days'. Each may be written singular or abbreviated to just the first letter.
  If no units are given and the numbers are unsigned, the units are assumed to
  be seconds.
This action requires Postgres 8.3 or better.
Example 1: Give a warning if any connection has been idle in transaction for
  more than 15 seconds:
  check_postgres_txn_idle --port=5432 --warning='15 seconds'
Example 2: Give a warning if there are 50 or more transactions
  check_postgres_txn_idle --port=5432 --warning='+50'
Example 3: Give a critical if 5 or more connections have been idle in
  transaction for more than 10 seconds:
  check_postgres_txn_idle --port=5432 --critical='5 for 10 seconds'
For MRTG output, returns the time in seconds the longest idle transaction has
  been running. The fourth line returns the name of the database and other
  information about the longest transaction.
txn_time¶
("symlink: check_postgres_txn_time") Checks the length of open
  transactions on one or more databases. There is no need to run this command
  more than once per database cluster. Databases can be filtered by use of the
  
--include and 
--exclude options. See the "BASIC
  FILTERING" section for more details. The owner of the transaction can
  also be filtered, by use of the 
--includeuser and 
--excludeuser
  options. See the "USER NAME FILTERING" section for more details.
The values or the 
--warning and 
--critical options are units of
  time, and must be provided (no default). Valid units are 'seconds', 'minutes',
  'hours', or 'days'. Each may be written singular or abbreviated to just the
  first letter. If no units are given, the units are assumed to be seconds.
This action requires Postgres 8.3 or better.
Example 1: Give a critical if any transaction has been open for more than 10
  minutes:
  check_postgres_txn_time --port=5432 --critical='10 minutes'
Example 1: Warn if user 'warehouse' has a transaction open over 30 seconds
  check_postgres_txn_time --port-5432 --warning=30s --includeuser=warehouse
For MRTG output, returns the maximum time in seconds a transaction has been open
  on the first line. The fourth line gives the name of the database.
txn_wraparound¶
("symlink: check_postgres_txn_wraparound") Checks how close to
  transaction wraparound one or more databases are getting. The 
--warning
  and 
--critical options indicate the number of transactions done, and
  must be a positive integer. If either option is not given, the default values
  of 1.3 and 1.4 billion are used. There is no need to run this command more
  than once per database cluster. For a more detailed discussion of what this
  number represents and what to do about it, please visit the page
  
http://www.postgresql.org/docs/current/static/routine-vacuuming.html#VACUUM-FOR-WRAPAROUND
  <
http://www.postgresql.org/docs/current/static/routine-vacuuming.html#VACUUM-FOR-WRAPAROUND>
The warning and critical values can have underscores in the number for
  legibility, as Perl does.
Example 1: Check the default values for the localhost database
  check_postgres_txn_wraparound --host=localhost
Example 2: Check port 6000 and give a critical when 1.7 billion transactions are
  hit:
  check_postgres_txn_wraparound --port=6000 --critical=1_700_000_000
For MRTG output, returns the highest number of transactions for all databases on
  line one, while line 4 indicates which database it is.
version¶
("symlink: check_postgres_version") Checks that the required version
  of Postgres is running. The 
--warning and 
--critical options
  (only one is required) must be of the format 
X.Y or 
X.Y.Z where
  
X is the major version number, 
Y is the minor version number,
  and 
Z is the revision.
Example 1: Give a warning if the database on port 5678 is not version 8.4.10:
  check_postgres_version --port=5678 -w=8.4.10
Example 2: Give a warning if any databases on hosts valley,grain, or sunshine is
  not 8.3:
  check_postgres_version -H valley,grain,sunshine --critical=8.3
For MRTG output, reports a 1 or a 0 indicating success or failure on the first
  line. The fourth line indicates the current version. The version must be
  provided via the "--mrtg" option.
wal_files¶
("symlink: check_postgres_wal_files") Checks how many WAL files exist
  in the 
pg_xlog directory, which is found off of your
  
data_directory, sometimes as a symlink to another physical disk for
  performance reasons. This action must be run as a superuser, in order to
  access the contents of the 
pg_xlog directory. The minimum version to
  use this action is Postgres 8.1. The 
--warning and 
--critical
  options are simply the number of files in the 
pg_xlog directory. What
  number to set this to will vary, but a general guideline is to put a number
  slightly higher than what is normally there, to catch problems early.
Normally, WAL files are closed and then re-used, but a long-running open
  transaction, or a faulty 
archive_command script, may cause Postgres to
  create too many files. Ultimately, this will cause the disk they are on to run
  out of space, at which point Postgres will shut down.
Example 1: Check that the number of WAL files is 20 or less on host
  "pluto"
  check_postgres_wal_files --host=pluto --critical=20
For MRTG output, reports the number of WAL files on line 1.
rebuild_symlinks¶
rebuild_symlinks_force¶
This action requires no other arguments, and does not connect to any databases,
  but simply creates symlinks in the current directory for each action, in the
  form 
check_postgres_<action_name>. If the file already exists, it
  will not be overwritten. If the action is rebuild_symlinks_force, then
  symlinks will be overwritten. The option --symlinks is a shorter way of saying
  --action=rebuild_symlinks
BASIC FILTERING¶
The options 
--include and 
--exclude can be combined to limit which
  things are checked, depending on the action. The name of the database can be
  filtered when using the following actions: backends, database_size, locks,
  query_time, txn_idle, and txn_time. The name of a relation can be filtered
  when using the following actions: bloat, index_size, table_size,
  relation_size, last_vacuum, last_autovacuum, last_analyze, and
  last_autoanalyze. The name of a setting can be filtered when using the
  settings_checksum action. The name of a file system can be filtered when using
  the disk_space action.
If only an include option is given, then ONLY those entries that match will be
  checked. However, if given both exclude and include, the exclusion is done
  first, and the inclusion after, to reinstate things that may have been
  excluded. Both 
--include and 
--exclude can be given multiple
  times, and/or as comma-separated lists. A leading tilde will match the
  following word as a regular expression.
To match a schema, end the search term with a single period. Leading tildes can
  be used for schemas as well.
Be careful when using filtering: an inclusion rule on the backends, for example,
  may report no problems not only because the matching database had no backends,
  but because you misspelled the name of the database!
Examples:
Only checks items named pg_class:
 --include=pg_class
Only checks items containing the letters 'pg_':
 --include=~pg_
Only check items beginning with 'pg_':
 --include=~^pg_
Exclude the item named 'test':
 --exclude=test
Exclude all items containing the letters 'test:
 --exclude=~test
Exclude all items in the schema 'pg_catalog':
 --exclude='pg_catalog.'
Exclude all items containing the letters 'ace', but allow the item 'faceoff':
 --exclude=~ace --include=faceoff
Exclude all items which start with the letters 'pg_', which contain the letters
  'slon', or which are named 'sql_settings' or 'green'. Specifically check items
  with the letters 'prod' in their names, and always check the item named
  'pg_relname':
 --exclude=~^pg_,~slon,sql_settings --exclude=green --include=~prod,pg_relname
USER NAME FILTERING¶
The options 
--includeuser and 
--excludeuser can be used on some
  actions to only examine database objects owned by (or not owned by) one or
  more users. An 
--includeuser option always trumps an
  
--excludeuser option. You can give each option more than once for
  multiple users, or you can give a comma-separated list. The actions that
  currently use these options are:
  - database_size
  - last_analyze
  - last_autoanalyze
  - last_vacuum
  - last_autovacuum
  - query_time
  - relation_size
  - txn_time
Examples:
Only check items owned by the user named greg:
 --includeuser=greg
Only check items owned by either watson or crick:
 --includeuser=watson,crick
Only check items owned by crick,franklin, watson, or wilkins:
 --includeuser=watson --includeuser=franklin --includeuser=crick,wilkins
Check all items except for those belonging to the user scott:
 --excludeuser=scott
TEST MODE¶
To help in setting things up, this program can be run in a "test mode"
  by specifying the 
--test option. This will perform some basic tests to
  make sure that the databases can be contacted, and that certain per-action
  prerequisites are met, such as whether the user is a superuser, if the version
  of Postgres is new enough, and if stats_row_level is enabled.
FILES¶
In addition to command-line configurations, you can put any options inside of a
  file. The file 
.check_postgresrc in the current directory will be used
  if found. If not found, then the file 
~/.check_postgresrc will be used.
  Finally, the file /etc/check_postgresrc will be used if available. The format
  of the file is option = value, one per line. Any line starting with a '#' will
  be skipped. Any values loaded from a check_postgresrc file will be overwritten
  by command-line options. All check_postgresrc files can be ignored by
  supplying a "--no-checkpostgresrc" argument.
ENVIRONMENT VARIABLES¶
The environment variable 
$ENV{HOME} is used to look for a
  
.check_postgresrc file.
TIPS AND TRICKS¶
Since this program uses the 
psql program, make sure it is accessible to
  the user running the script. If run as a cronjob, this often means modifying
  the 
PATH environment variable.
If you are using Nagios in embedded Perl mode, use the "--action"
  argument instead of symlinks, so that the plugin only gets compiled one time.
DEPENDENCIES¶
Access to a working version of psql, and the following very standard Perl
  modules:
  - Cwd
  - Getopt::Long
  - File::Basename
  - File::Temp
  - Time::HiRes (if $opt{showtime} is set to true, which
    is the default)
The "settings_checksum" action requires the 
Digest::MD5 module.
The "checkpoint" action requires the 
Date::Parse module.
Some actions require access to external programs. If psql is not explicitly
  specified, the command 
"which" is used to find
  it. The program 
"/bin/df" is needed by the
  "disk_space" action.
DEVELOPMENT¶
Development happens using the git system. You can clone the latest version by
  doing:
 git clone git://bucardo.org/check_postgres.git
MAILING LIST¶
Three mailing lists are available. For discussions about the program, bug
  reports, feature requests, and commit notices, send email to
  check_postgres@bucardo.org
https://mail.endcrypt.com/mailman/listinfo/check_postgres
A low-volume list for announcement of new versions and important notices is the
  'check_postgres-announce' list:
https://mail.endcrypt.com/mailman/listinfo/check_postgres-announce
Source code changes (via git-commit) are sent to the 'check_postgres-commit'
  list:
https://mail.endcrypt.com/mailman/listinfo/check_postgres-commit
HISTORY¶
Items not specifically attributed are by GSM (Greg Sabino Mullane).
  - Version 2.19.0 January 17, 2012
- 
      Add the --assume-prod option (CA~Xdric Villemain)
  Add the cluster_id check (CA~Xdric Villemain)
  Improve settings_checksum and checkpoint tests (CA~Xdric Villemain)
  Do no do an inner join to pg_user when checking database size
    (Greg Sabino Mullane; reported by Emmanuel Lesouef)
  Use the full path when getting sequence information for same_schema.
    (Greg Sabino Mullane; reported by Cindy Wise)
  Fix the formula for calculating xlog positions (Euler Taveira de Oliveira)
  Better ordering of output for bloat check - make indexes as important
    as tables (Greg Sabino Mullane; reported by Jens Wilke)
  Show the dbservice if it was used at top of same_schema output
    (Mike Blackwell)
  Better installation paths (Greg Sabino Mullane, per bug 53)
    
  - Version 2.18.0 October 2, 2011
- 
      Redo the same_schema action. Use new --filter argument for all filtering.
  Allow comparisons between any number of databases.
  Remove the dbname2, dbport2, etc. arguments.
  Allow comparison of the same db over time.
  Swap db1 and db2 if the slave is 1 for the hot standby check (David E. Wheeler)
  Allow multiple --schema arguments for the slony_status action (GSM and Jehan-Guillaume de Rorthais)
  Fix ORDER BY in the last vacuum/analyze action (Nicolas Thauvin)
  Fix check_hot_standby_delay perfdata output (Nicolas Thauvin)
  Look in the correct place for the .ready files with the archive_ready action (Nicolas Thauvin)
  New action: commitratio (Guillaume Lelarge)
  New action: hitratio (Guillaume Lelarge)
  Make sure --action overrides the symlink naming trick.
  Set defaults for archive_ready and wal_files (Thomas Guettler, GSM)
  Better output for wal_files and archive_ready (GSM)
  Fix warning when client_port set to empty string (bug #79)
  Account for "empty row" in -x output (i.e. source of functions).
  Fix some incorrectly named data fields (Andy Lester)
  Expand the number of pgbouncer actions (Ruslan Kabalin)
  Give detailed information and refactor txn_idle, txn_time, and query_time
    (Per request from bug #61)
  Set maxalign to 8 in the bloat check if box identified as '64-bit'
    (Michel Sijmons, bug #66)
  Support non-standard version strings in the bloat check.
    (Michel Sijmons and Gurjeet Singh, bug #66)
  Do not show excluded databases in some output (Ruslan Kabalin)
  Allow "and", "or" inside arguments (David E. Wheeler)
  Add the "new_version_box" action.
  Fix psql version regex (Peter Eisentraut, bug #69)
  Add the --assume-standby-mode option (Ruslan Kabalin)
  Note that txn_idle and query_time require 8.3 (Thomas Guettler)
  Standardize and clean up all perfdata output (bug #52)
  Exclude "idle in transaction" from the query_time check (bug #43)
  Fix the perflimit for the bloat action (bug #50)
  Clean up the custom_query action a bit.
  Fix space in perfdata for hot_standby_delay action (Nicolas Thauvin)
  Handle undef percents in check_fsm_relations (Andy Lester)
  Fix typo in dbstats action (Stas Vitkovsky)
  Fix MRTG for last vacuum and last_analyze actions.
    
  - Version 2.17.0 no public release
  - Version 2.16.0 January 20, 2011
- 
      Add new action 'hot_standby_delay' (Nicolas Thauvin)
  Add cache-busting for the version-grabbing utilities.
  Fix problem with going to next method for new_version_pg
    (Greg Sabino Mullane, reported by Hywel Mallett in bug #65)
  Allow /usr/local/etc as an alternative location for the 
    check_postgresrc file (Hywel Mallett)
  Do not use tgisconstraint in same_schema if Postgres >= 9
    (Guillaume Lelarge)
    
  - Version 2.15.4 January 3, 2011
- 
      Fix warning when using symlinks
    (Greg Sabino Mullane, reported by Peter Eisentraut in bug #63)
    
  - Version 2.15.3 December 30, 2010
- 
      Show OK for no matching txn_idle entries.
    
  - Version 2.15.2 December 28, 2010
- 
      Better formatting of sizes in the bloat action output.
  Remove duplicate perfs in bloat action output.
    
  - Version 2.15.1 December 27, 2010
- 
      Fix problem when examining items in pg_settings (Greg Sabino Mullane)
  For connection test, return critical, not unknown, on FATAL errors
    (Greg Sabino Mullane, reported by Peter Eisentraut in bug #62)
    
  - Version 2.15.0 November 8, 2010
- 
      Add --quiet argument to suppress output on OK Nagios results
  Add index comparison for same_schema (Norman Yamada and Greg Sabino Mullane)
  Use $ENV{PGSERVICE} instead of "service=" to prevent problems (Guillaume Lelarge)
  Add --man option to show the entire manual. (Andy Lester)
  Redo the internal run_command() sub to use -x and hashes instead of regexes.
  Fix error in custom logic (Andreas Mager)
  Add the "pgbouncer_checksum" action (Guillaume Lelarge)
  Fix regex to work on WIN32 for check_fsm_relations and check_fsm_pages (Luke Koops)
  Don't apply a LIMIT when using --exclude on the bloat action (Marti Raudsepp)
  Change the output of query_time to show pid,user,port, and address (Giles Westwood)
  Fix to show database properly when using slony_status (Guillaume Lelarge)
  Allow warning items for same_schema to be comma-separated (Guillaume Lelarge)
  Constraint definitions across Postgres versions match better in same_schema.
  Work against "EnterpriseDB" databases (Sivakumar Krishnamurthy and Greg Sabino Mullane)
  Separate perfdata with spaces (Jehan-Guillaume (ioguix) de Rorthais)
  Add new action "archive_ready" (Jehan-Guillaume (ioguix) de Rorthais)
    
  - Version 2.14.3 (March 1, 2010)
- 
      Allow slony_status action to handle more than one slave.
  Use commas to separate function args in same_schema output (Robert Treat)
    
  - Version 2.14.2 (February 18, 2010)
- 
      Change autovac_freeze default warn/critical back to 90%/95% (Robert Treat)
  Put all items one-per-line for relation size actions if --verbose=1
    
  - Version 2.14.1 (February 17, 2010)
- 
      Don't use $^T in logfile check, as script may be long-running
  Change the error string for the logfile action for easier exclusion
    by programs like tail_n_mail
    
  - Version 2.14.0 (February 11, 2010)
- 
      Added the 'slony_status' action.
  Changed the logfile sleep from 0.5 to 1, as 0.5 gets rounded to 0 on some boxes!
    
  - Version 2.13.2 (February 4, 2010)
- 
      Allow timeout option to be used for logtime 'sleep' time.
    
  - Version 2.13.2 (February 4, 2010)
- 
      Show offending database for query_time action.
  Apply perflimit to main output for sequence action.
  Add 'noowner' option to same_schema action.
  Raise sleep timeout for logfile check to 15 seconds.
    
  - Version 2.13.1 (February 2, 2010)
- 
      Fix bug preventing column constraint differences from 2 > 1 for same_schema from being shown.
  Allow aliases 'dbname1', 'dbhost1', 'dbport1',etc.
  Added "nolanguage" as a filter for the same_schema option.
  Don't track "generic" table constraints (e.. $1, $2) using same_schema
    
  - Version 2.13.0 (January 29, 2010)
- 
      Allow "nofunctions" as a filter for the same_schema option.
  Added "noperm" as a filter for the same_schema option.
  Ignore dropped columns when considered positions for same_schema (Guillaume Lelarge)
    
  - Version 2.12.1 (December 3, 2009)
- 
      Change autovac_freeze default warn/critical from 90%/95% to 105%/120% (Marti Raudsepp)
    
  - Version 2.12.0 (December 3, 2009)
- 
      Allow the temporary directory to be specified via the "tempdir" argument,
    for systems that need it (e.g. /tmp is not owned by root).
  Fix so old versions of Postgres (< 8.0) use the correct default database (Giles Westwood)
  For "same_schema" trigger mismatches, show the attached table.
  Add the new_version_bc check for Bucardo version checking.
  Add database name to perf output for last_vacuum|analyze (Guillaume Lelarge)
  Fix for bloat action against old versions of Postgres without the 'block_size' param.
    
  - Version 2.11.1 (August 27, 2009)
- 
      Proper Nagios output for last_vacuum|analyze actions. (CA~Xdric Villemain)
  Proper Nagios output for locks action. (CA~Xdric Villemain)
  Proper Nagios output for txn_wraparound action. (CA~Xdric Villemain)
  Fix for constraints with embedded newlines for same_schema.
  Allow --exclude for all items when using same_schema.
    
  - Version 2.11.0 (August 23, 2009)
- 
      Add Nagios perf output to the wal_files check (CA~Xdric Villemain)
  Add support for .check_postgresrc, per request from Albe Laurenz.
  Allow list of web fetch methods to be changed with the --get_method option.
  Add support for the --language argument, which overrides any ENV.
  Add the --no-check_postgresrc flag.
  Ensure check_postgresrc options are completely overridden by command-line options.
  Fix incorrect warning > critical logic in replicate_rows (Glyn Astill)
    
  - Version 2.10.0 (August 3, 2009)
- 
      For same_schema, compare view definitions, and compare languages.
  Make script into a global executable via the Makefile.PL file.
  Better output when comparing two databases.
  Proper Nagios output syntax for autovac_freeze and backends checks (CA~Xdric Villemain)
    
  - Version 2.9.5 (July 24, 2009)
- 
      Don't use a LIMIT in check_bloat if --include is used. Per complaint from Jeff Frost.
    
  - Version 2.9.4 (July 21, 2009)
- 
      More French translations (Guillaume Lelarge)
    
  - Version 2.9.3 (July 14, 2009)
- 
      Quote dbname in perf output for the backends check. (Davide Abrigo)
  Add 'fetch' as an alternative method for new_version checks, as this 
    comes by default with FreeBSD. (Hywel Mallett)
    
  - Version 2.9.2 (July 12, 2009)
- 
      Allow dots and dashes in database name for the backends check (Davide Abrigo)
  Check and display the database for each match in the bloat check (CA~Xdric Villemain)
  Handle 'too many connections' FATAL error in the backends check with a critical,
    rather than a generic error (Greg, idea by JA~Xrgen Schulz-BrA~Xssel)
  Do not allow perflimit to interfere with exclusion rules in the vacuum and 
    analyze tests. (Greg, bug reported by Jeff Frost)
    
  - Version 2.9.1 (June 12, 2009)
- 
      Fix for multiple databases with the check_bloat action (Mark Kirkwood)
  Fixes and improvements to the same_schema action (Jeff Boes)
  Write tests for same_schema, other minor test fixes (Jeff Boes)
    
  - Version 2.9.0 (May 28, 2009)
- 
      Added the same_schema action (Greg)
    
  - Version 2.8.1 (May 15, 2009)
- 
      Added timeout via statement_timeout in addition to perl alarm (Greg)
    
  - Version 2.8.0 (May 4, 2009)
- 
      Added internationalization support (Greg)
  Added the 'disabled_triggers' check (Greg)
  Added the 'prepared_txns' check (Greg)
  Added the 'new_version_cp' and 'new_version_pg' checks (Greg)
  French translations (Guillaume Lelarge)
  Make the backends search return ok if no matches due to inclusion rules,
    per report by Guillaume Lelarge (Greg)
  Added comprehensive unit tests (Greg, Jeff Boes, Selena Deckelmann)
  Make fsm_pages and fsm_relations handle 8.4 servers smoothly. (Greg)
  Fix missing 'upd' field in show_dbstats (Andras Fabian)
  Allow ENV{PGCONTROLDATA} and ENV{PGBINDIR}. (Greg)
  Add various Perl module infrastructure (e.g. Makefile.PL) (Greg)
  Fix incorrect regex in txn_wraparound (Greg)
  For txn_wraparound: consistent ordering and fix duplicates in perf output (Andras Fabian)
  Add in missing exabyte regex check (Selena Deckelmann)
  Set stats to zero if we bail early due to USERWHERECLAUSE (Andras Fabian)
  Add additional items to dbstats output (Andras Fabian)
  Remove --schema option from the fsm_ checks. (Greg Mullane and Robert Treat)
  Handle case when ENV{PGUSER} is set. (Andy Lester)
  Many various fixes. (Jeff Boes)
  Fix --dbservice: check version and use ENV{PGSERVICE} for old versions (CA~Xdric Villemain)
    
  - Version 2.7.3 (February 10, 2009)
- 
      Make the sequence action check if sequence being used for a int4 column and
  react appropriately. (Michael Glaesemann)
    
  - Version 2.7.2 (February 9, 2009)
- 
      Fix to prevent multiple groupings if db arguments given.
    
  - Version 2.7.1 (February 6, 2009)
- 
      Allow the -p argument for port to work again.
    
  - Version 2.7.0 (February 4, 2009)
- 
      Do not require a connection argument, but use defaults and ENV variables when 
    possible: PGHOST, PGPORT, PGUSER, PGDATABASE.
    
  - Version 2.6.1 (February 4, 2009)
- 
      Only require Date::Parse to be loaded if using the checkpoint action.
    
  - Version 2.6.0 (January 26, 2009)
- 
      Add the 'checkpoint' action.
    
  - Version 2.5.4 (January 7, 2009)
- 
      Better checking of $opt{dbservice} structure (CA~Xdric Villemain)
  Fix time display in timesync action output (Selena Deckelmann)
  Fix documentation typos (Josh Tolley)
    
  - Version 2.5.3 (December 17, 2008)
- 
      Minor fix to regex in verify_version (Lee Jensen)
    
  - Version 2.5.2 (December 16, 2008)
- 
      Minor documentation tweak.
    
  - Version 2.5.1 (December 11, 2008)
- 
      Add support for --noidle flag to prevent backends action from counting idle processes.
  Patch by Selena Deckelmann.
  Fix small undefined warning when not using --dbservice.
    
  - Version 2.5.0 (December 4, 2008)
- 
      Add support for the pg_Service.conf file with the --dbservice option.
    
  - Version 2.4.3 (November 7, 2008)
- 
      Fix options for replicate_row action, per report from Jason Gordon.
    
  - Version 2.4.2 (November 6, 2008)
- 
      Wrap File::Temp::cleanup() calls in eval, in case File::Temp is an older version.
  Patch by Chris Butler.
    
  - Version 2.4.1 (November 5, 2008)
- 
      Cast numbers to numeric to support sequences ranges > bigint in check_sequence action.
  Thanks to Scott Marlowe for reporting this.
    
  - Version 2.4.0 (October 26, 2008)
- 
     Add Cacti support with the dbstats action.
 Pretty up the time output for last vacuum and analyze actions.
 Show the percentage of backends on the check_backends action.
    
  - Version 2.3.10 (October 23, 2008)
- 
     Fix minor warning in action check_bloat with multiple databases.
 Allow warning to be greater than critical when using the --reverse option.
 Support the --perflimit option for the check_sequence action.
    
  - Version 2.3.9 (October 23, 2008)
- 
     Minor tweak to way we store the default port.
    
  - Version 2.3.8 (October 21, 2008)
- 
     Allow the default port to be changed easily.
 Allow transform of simple output by MB, GB, etc.
    
  - Version 2.3.7 (October 14, 2008)
- 
     Allow multiple databases in 'sequence' action. Reported by Christoph Zwerschke.
    
  - Version 2.3.6 (October 13, 2008)
- 
     Add missing $schema to check_fsm_pages. (Robert Treat)
    
  - Version 2.3.5 (October 9, 2008)
- 
     Change option 'checktype' to 'valtype' to prevent collisions with -c[ritical]
 Better handling of errors.
    
  - Version 2.3.4 (October 9, 2008)
- 
     Do explicit cleanups of the temp directory, per problems reported by sb@nnx.com.
    
  - Version 2.3.3 (October 8, 2008)
- 
     Account for cases where some rounding queries give -0 instead of 0.
 Thanks to Glyn Astill for helping to track this down.
    
  - Version 2.3.2 (October 8, 2008)
- 
     Always quote identifiers in check_replicate_row action.
    
  - Version 2.3.1 (October 7, 2008)
- 
     Give a better error if one of the databases cannot be reached.
    
  - Version 2.3.0 (October 4, 2008)
- 
     Add the "sequence" action, thanks to Gavin M. Roy for the idea.
 Fix minor problem with autovac_freeze action when using MRTG output.
 Allow output argument to be case-insensitive.
 Documentation fixes.
    
  - Version 2.2.4 (October 3, 2008)
- 
     Fix some minor typos
    
  - Version 2.2.3 (October 1, 2008)
- 
     Expand range of allowed names for --repinfo argument (Glyn Astill)
 Documentation tweaks.
    
  - Version 2.2.2 (September 30, 2008)
- 
     Fixes for minor output and scoping problems.
    
  - Version 2.2.1 (September 28, 2008)
- 
     Add MRTG output to fsm_pages and fsm_relations.
 Force error messages to one-line for proper Nagios output.
 Check for invalid prereqs on failed command. From conversations with Euler Taveira de Oliveira.
 Tweak the fsm_pages formula a little.
    
  - Version 2.2.0 (September 25, 2008)
- 
     Add fsm_pages and fsm_relations actions. (Robert Treat)
    
  - Version 2.1.4 (September 22, 2008)
- 
     Fix for race condition in txn_time action.
 Add --debugoutput option.
    
  - Version 2.1.3 (September 22, 2008)
- 
     Allow alternate arguments "dbhost" for "host" and "dbport" for "port".
 Output a zero as default value for second line of MRTG output.
    
  - Version 2.1.2 (July 28, 2008)
- 
     Fix sorting error in the "disk_space" action for non-Nagios output.
 Allow --simple as a shortcut for --output=simple.
    
  - Version 2.1.1 (July 22, 2008)
- 
     Don't check databases with datallowconn false for the "autovac_freeze" action.
    
  - Version 2.1.0 (July 18, 2008)
- 
     Add the "autovac_freeze" action, thanks to Robert Treat for the idea and design.
 Put an ORDER BY on the "txn_wraparound" action.
    
  - Version 2.0.1 (July 16, 2008)
- 
     Optimizations to speed up the "bloat" action quite a bit.
 Fix "version" action to not always output in mrtg mode.
    
  - Version 2.0.0 (July 15, 2008)
- 
     Add support for MRTG and "simple" output options.
 Many small improvements to nearly all actions.
    
  - Version 1.9.1 (June 24, 2008)
- 
     Fix an error in the bloat SQL in 1.9.0
 Allow percentage arguments to be over 99%
 Allow percentages in the bloat --warning and --critical (thanks to Robert Treat for the idea)
    
  - Version 1.9.0 (June 22, 2008)
- 
     Don't include information_schema in certain checks. (Jeff Frost)
 Allow --include and --exclude to use schemas by using a trailing period.
    
  - Version 1.8.5 (June 22, 2008)
- 
     Output schema name before table name where appropriate.
 Thanks to Jeff Frost.
    
  - Version 1.8.4 (June 19, 2008)
- 
     Better detection of problems in --replicate_row.
    
  - Version 1.8.3 (June 18, 2008)
- 
     Fix 'backends' action: there may be no rows in pg_stat_activity, so run a second
   query if needed to find the max_connections setting.
 Thanks to Jeff Frost for the bug report.
    
  - Version 1.8.2 (June 10, 2008)
- 
     Changes to allow working under Nagios' embedded Perl mode. (Ioannis Tambouras)
    
  - Version 1.8.1 (June 9, 2008)
- 
     Allow 'bloat' action to work on Postgres version 8.0.
 Allow for different commands to be run for each action depending on the server version.
 Give better warnings when running actions not available on older Postgres servers.
    
  - Version 1.8.0 (June 3, 2008)
- 
     Add the --reverse option to the custom_query action.
    
  - Version 1.7.1 (June 2, 2008)
- 
     Fix 'query_time' action: account for race condition in which zero rows appear in pg_stat_activity.
 Thanks to Dustin Black for the bug report.
    
  - Version 1.7.0 (May 11, 2008)
- 
     Add --replicate_row action
    
  - Version 1.6.1 (May 11, 2008)
- 
     Add --symlinks option as a shortcut to --action=rebuild_symlinks
    
  - Version 1.6.0 (May 11, 2008)
- 
     Add the custom_query action.
    
  - Version 1.5.2 (May 2, 2008)
- 
     Fix problem with too eager creation of custom pgpass file.
    
  - Version 1.5.1 (April 17, 2008)
- 
     Add example Nagios configuration settings (Brian A. Seklecki)
    
  - Version 1.5.0 (April 16, 2008)
- 
     Add the --includeuser and --excludeuser options. Documentation cleanup.
    
  - Version 1.4.3 (April 16, 2008)
- 
     Add in the 'output' concept for future support of non-Nagios programs.
    
  - Version 1.4.2 (April 8, 2008)
- 
     Fix bug preventing --dbpass argument from working (Robert Treat).
    
  - Version 1.4.1 (April 4, 2008)
- 
     Minor documentation fixes.
    
  - Version 1.4.0 (April 2, 2008)
- 
     Have 'wal_files' action use pg_ls_dir (idea by Robert Treat).
 For last_vacuum and last_analyze, respect autovacuum effects, add separate 
   autovacuum checks (ideas by Robert Treat).
    
  - Version 1.3.1 (April 2, 2008)
- 
     Have txn_idle use query_start, not xact_start.
    
  - Version 1.3.0 (March 23, 2008)
- 
     Add in txn_idle and txn_time actions.
    
  - Version 1.2.0 (February 21, 2008)
- 
     Add the 'wal_files' action, which counts the number of WAL files
   in your pg_xlog directory.
 Fix some typos in the docs.
 Explicitly allow -v as an argument.
 Allow for a null syslog_facility in the 'logfile' action.
    
  - Version 1.1.2 (February 5, 2008)
- 
     Fix error preventing --action=rebuild_symlinks from working.
    
  - Version 1.1.1 (February 3, 2008)
- 
     Switch vacuum and analyze date output to use 'DD', not 'D'. (Glyn Astill)
    
  - Version 1.1.0 (December 16, 2008)
- 
     Fixes, enhancements, and performance tracking.
 Add performance data tracking via --showperf and --perflimit
 Lots of refactoring and cleanup of how actions handle arguments.
 Do basic checks to figure out syslog file for 'logfile' action.
 Allow for exact matching of beta versions with 'version' action.
 Redo the default arguments to only populate when neither 'warning' nor 'critical' is provided.
 Allow just warning OR critical to be given for the 'timesync' action.
 Remove 'redirect_stderr' requirement from 'logfile' due to 8.3 changes.
 Actions 'last_vacuum' and 'last_analyze' are 8.2 only (Robert Treat)
    
  - Version 1.0.16 (December 7, 2007)
- 
     First public release, December 2007
    
BUGS AND LIMITATIONS¶
The index bloat size optimization is rough.
Some actions may not work on older versions of Postgres (before 8.0).
Please report any problems to check_postgres@bucardo.org
AUTHOR¶
Greg Sabino Mullane <greg@endpoint.com>
NAGIOS EXAMPLES¶
Some example Nagios configuration settings using this script:
 define command {
     command_name    check_postgres_size
     command_line    $USER2$/check_postgres -H $HOSTADDRESS$ -u pgsql -db postgres --action database_size -w $ARG1$ -c $ARG2$
 }
 define command {
     command_name    check_postgres_locks
     command_line    $USER2$/check_postgres -H $HOSTADDRESS$ -u pgsql -db postgres --action locks -w $ARG1$ -c $ARG2$
 }
 define service {
     use                    generic-other
     host_name              dbhost.gtld
     service_description    dbhost PostgreSQL Service Database Usage Size
     check_command          check_postgres_size!256000000!512000000
 }
 define service {
     use                    generic-other
     host_name              dbhost.gtld
     service_description    dbhost PostgreSQL Service Database Locks
     check_command          check_postgres_locks!2!3
 }
LICENSE AND COPYRIGHT¶
Copyright (c) 2007-2012 Greg Sabino Mullane <greg@endpoint.com>.
Redistribution and use in source and binary forms, with or without modification,
  are permitted provided that the following conditions are met:
  1. Redistributions of source code must retain the above copyright notice, 
     this list of conditions and the following disclaimer.
  2. Redistributions in binary form must reproduce the above copyright notice, 
     this list of conditions and the following disclaimer in the documentation 
     and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
  IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
  EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
  IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  POSSIBILITY OF SUCH DAMAGE.