Scroll to navigation

SYSTEMD-CRYPTSETUP-GENERATOR(8) systemd-cryptsetup-generator SYSTEMD-CRYPTSETUP-GENERATOR(8)

NAME

systemd-cryptsetup-generator - Unit generator for /etc/crypttab

SYNOPSIS

/lib/systemd/system-generators/systemd-cryptsetup-generator

DESCRIPTION

systemd-cryptsetup-generator is a generator that translates /etc/crypttab into native systemd units early at boot and when configuration of the system manager is reloaded. This will create systemd-cryptsetup@.service(8) units as necessary.

systemd-cryptsetup-generator implements systemd.generator(7).

KERNEL COMMAND LINE

systemd-cryptsetup-generator understands the following kernel command line parameters:

luks=, rd.luks=

Takes a boolean argument. Defaults to "yes". If "no", disables the generator entirely. rd.luks= is honored only by initial RAM disk (initrd) while luks= is honored by both the main system and the initrd.

luks.crypttab=, rd.luks.crypttab=

Takes a boolean argument. Defaults to "yes". If "no", causes the generator to ignore any devices configured in /etc/crypttab (luks.uuid= will still work however). rd.luks.crypttab= is honored only by initial RAM disk (initrd) while luks.crypttab= is honored by both the main system and the initrd.

luks.uuid=, rd.luks.uuid=

Takes a LUKS superblock UUID as argument. This will activate the specified device as part of the boot process as if it was listed in /etc/crypttab. This option may be specified more than once in order to set up multiple devices. rd.luks.uuid= is honored only by initial RAM disk (initrd) while luks.uuid= is honored by both the main system and the initrd.

If /etc/crypttab contains entries with the same UUID, then the name, keyfile and options specified there will be used. Otherwise, the device will have the name "luks-UUID".

If /etc/crypttab exists, only those UUIDs specified on the kernel command line will be activated in the initrd or the real root.

luks.name=, rd.luks.name=

Takes a LUKS super block UUID followed by an "=" and a name. This implies rd.luks.uuid= or luks.uuid= and will additionally make the LUKS device given by the UUID appear under the provided name.

rd.luks.name= is honored only by initial RAM disk (initrd) while luks.name= is honored by both the main system and the initrd.

luks.options=, rd.luks.options=

Takes a LUKS super block UUID followed by an "=" and a string of options separated by commas as argument. This will override the options for the given UUID.

If only a list of options, without an UUID, is specified, they apply to any UUIDs not specified elsewhere, and without an entry in /etc/crypttab.

rd.luks.options= is honored only by initial RAM disk (initrd) while luks.options= is honored by both the main system and the initrd.

luks.key=, rd.luks.key=

Takes a password file name as argument or a LUKS super block UUID followed by a "=" and a password file name.

For those entries specified with rd.luks.uuid= or luks.uuid=, the password file will be set to the one specified by rd.luks.key= or luks.key= of the corresponding UUID, or the password file that was specified without a UUID.

It is also possible to specify an external device which should be mounted before we attempt to unlock the LUKS device. systemd-cryptsetup will use password file stored on that device. Device containing password file is specified by appending colon and a device identifier to the password file path. For example, rd.luks.uuid=b40f1abf-2a53-400a-889a-2eccc27eaa40 rd.luks.key=b40f1abf-2a53-400a-889a-2eccc27eaa40=/keyfile:LABEL=keydev. Hence, in this case, we will attempt to mount file system residing on the block device with label "keydev". This syntax is for now only supported on a per-device basis, i.e. you have to specify LUKS device UUID.

rd.luks.key= is honored only by initial RAM disk (initrd) while luks.key= is honored by both the main system and the initrd.

SEE ALSO

systemd(1), crypttab(5), systemd-cryptsetup@.service(8), cryptsetup(8), systemd-fstab-generator(8)
systemd 241