NAME¶
dgrcla - DGR-based BP convergence layer adapter (input and output) task
SYNOPSIS¶
dgrcla local_hostname[:
local_port_nbr]
DESCRIPTION¶
dgrcla is a background "daemon" task that spawns two threads,
one that handles DGR convergence layer protocol input and a second that
handles DGR convergence layer protocol output.
The input thread receives DGR messages via a UDP socket bound to
local_hostname and
local_port_nbr, extracts bundles from those
messages, and passes them to the bundle protocol agent on the local ION node.
(
local_port_nbr defaults to 1113 if not specified.)
The output thread extracts bundles from the queues of bundles ready for
transmission via DGR to remote bundle protocol agents, encapsulates them in
DGR messages, and sends those messages to the appropriate remote UDP sockets
as indicated by the host names and UDP port numbers (destination induct names)
associated with the bundles by the routing daemons that enqueued them.
Note that
dgrcla is a "promiscuous" convergence layer daemon,
able to transmit bundles to any DGR destination induct. Its duct name is the
name of the corresponding induct, rather than the induct name of any single
DGR destination induct to which it might be dedicated, so scheme configuration
directives that cite this outduct must provide destination induct IDs. For the
DGR convergence-layer protocol, destination induct IDs are identical to induct
names, i.e., they are of the form
local_hostname[:
local_port_nbr].
dgrcla is spawned automatically by
bpadmin in response to the 's'
(START) command that starts operation of the Bundle Protocol, and it is
terminated by
bpadmin in response to an 'x' (STOP) command.
dgrcla can also be spawned and terminated in response to START and STOP
commands that pertain specifically to the DGR convergence layer protocol.
EXIT STATUS¶
- 0
- dgrcla terminated normally, for reasons noted in the
ion.log file. If this termination was not commanded, investigate
and solve the problem identified in the log file and use bpadmin to
restart dgrcla.
- 1
- dgrcla terminated abnormally, for reasons noted in
the ion.log file. Investigate and solve the problem identified in
the log file, then use bpadmin to restart dgrcla.
FILES¶
No configuration files are needed.
ENVIRONMENT¶
No environment variables apply.
DIAGNOSTICS¶
The following diagnostics may be issued to the
ion.log log file:
- dgrcla can't attach to BP.
- bpadmin has not yet initialized Bundle Protocol
operations.
- No such dgr induct.
- No DGR induct with duct name matching local_hostname
and local_port_nbr has been added to the BP database. Use
bpadmin to stop the DGR convergence-layer protocol, add the induct,
and then restart the DGR protocol.
- CLI task is already started for this engine.
- Redundant initiation of dgrcla.
- No such dgr induct.
- No DGR outduct with duct name matching
local_hostname and local_port_nbr has been added to the BP
database. Use bpadmin to stop the DGR convergence-layer protocol,
add the outduct, and then restart the DGR protocol.
- Can't get IP address for host
- Operating system error. Check errtext, correct problem, and
restart DGR.
- dgrcla can't open DGR service access point.
- DGR system error. Check prior messages in ion.log
log file, correct problem, and then stop and restart the DGR
protocol.
- dgrcla can't create sender thread
- Operating system error. Check errtext, correct problem, and
restart DGR.
- dgrcla can't create receiver thread
- Operating system error. Check errtext, correct problem, and
restart DGR.
BUGS¶
Report bugs to <ion-bugs@korgano.eecs.ohiou.edu>
SEE ALSO¶
bpadmin(1),
bprc(5)