cryptsetup-generator(8) - Linux manual page (original) (raw)
SYSTEMD-...ENERATOR(8) systemd-cryptsetup-generator_SYSTEMD-...ENERATOR_(8)
NAME top
systemd-cryptsetup-generator - Unit generator for /etc/crypttabSYNOPSIS top
/usr/lib/systemd/system-generators/systemd-cryptsetup-generatorDESCRIPTION top
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)](../man8/systemd-cryptsetup@.service.8.html) units as necessary.
systemd-cryptsetup-generator implements [systemd.generator(7)](../man7/systemd.generator.7.html).KERNEL COMMAND LINE top
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 in the
initrd while _luks=_ is honored by both the main system and in
the initrd.
Added in version 186.
_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 in initrd while
_luks.crypttab=_ is honored by both the main system and in the
initrd.
Added in version 186.
_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 in the initrd, while _luks.uuid=_ is honored by
both the main system and in 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.
Added in version 186.
_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.
This parameter is the analogue of the first [crypttab(5)](../man5/crypttab.5.html) field
_volume-name_.
_rd.luks.name=_ is honored only in the initrd, while _luks.name=_
is honored by both the main system and in the initrd.
Added in version 218.
_luks.data=_, _rd.luks.data=_
Takes a LUKS super block UUID followed by a "=" and a block
device specification for device hosting encrypted data.
For those entries specified with _rd.luks.uuid=_ or _luks.uuid=_,
the data device will be set to the one specified by
_rd.luks.data=_ or _luks.data=_ of the corresponding UUID.
LUKS data device parameter is useful for specifying encrypted
data devices with detached headers specified in _luks.options_
entry containing "header=" argument. For example,
_rd.luks.uuid=_b40f1abf-2a53-400a-889a-2eccc27eaa40
_rd.luks.options=_b40f1abf-2a53-400a-889a-2eccc27eaa40=header=/path/to/luks.hdr
_rd.luks.data=_b40f1abf-2a53-400a-889a-2eccc27eaa40=/dev/sdx.
Hence, in this case, we will attempt to unlock LUKS device
assembled from data device "/dev/sdx" and LUKS header
(metadata) put in "/path/to/luks.hdr" file. This syntax is for
now only supported on a per-device basis, i.e. you have to
specify LUKS device UUID.
This parameter is the analogue of the second [crypttab(5)](../man5/crypttab.5.html) field
_encrypted-device_.
_rd.luks.data=_ is honored only in the initrd, while _luks.data=_
is honored by both the main system and in the initrd.
Added in version 247.
_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.
This parameter is the analogue of the third [crypttab(5)](../man5/crypttab.5.html) field
_key-file_.
_rd.luks.key=_ is honored only in the initrd, while _luks.key=_ is
honored by both the main system and in the initrd.
Added in version 202.
_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 a UUID, is specified, they
apply to any UUIDs not specified elsewhere, and without an
entry in /etc/crypttab.
This parameter is the analogue of the fourth [crypttab(5)](../man5/crypttab.5.html) field
_options_.
It is possible to specify an external device which should be
mounted before we attempt to unlock the LUKS device.
systemd-cryptsetup will assemble LUKS device by combining data
device specified in _luks.data_ with detached LUKS header found
in "header=" argument. For example,
_rd.luks.uuid=_b40f1abf-2a53-400a-889a-2eccc27eaa40
_rd.luks.options=_b40f1abf-2a53-400a-889a-2eccc27eaa40=header=/luks.hdr:LABEL=hdrdev
_rd.luks.data=_b40f1abf-2a53-400a-889a-2eccc27eaa40=/dev/sdx.
Hence, in this case, we will attempt to mount file system
residing on the block device with label "hdrdev", and look for
"luks.hdr" on that file system. Said header will be used to
unlock (decrypt) encrypted data stored on /dev/sdx. This
syntax is for now only supported on a per-device basis, i.e.
you have to specify LUKS device UUID.
_rd.luks.options=_ is honored only by initial RAM disk (initrd)
while _luks.options=_ is honored by both the main system and in
the initrd.
Added in version 208.SEE ALSO top
[systemd(1)](../man1/systemd.1.html), [crypttab(5)](../man5/crypttab.5.html), [systemd-cryptsetup@.service(8)](../man8/systemd-cryptsetup@.service.8.html),
[systemd-cryptenroll(1)](../man1/systemd-cryptenroll.1.html), [cryptsetup(8)](../man8/cryptsetup.8.html), [systemd-fstab-generator(8)](../man8/systemd-fstab-generator.8.html)COLOPHON top
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man-pages@man7.orgsystemd 258~devel SYSTEMD-...ENERATOR(8)
Pages that refer to this page:crypttab(5), kernel-command-line(7), systemd.directives(7), systemd.generator(7), systemd.index(7), systemd-cryptsetup(8), systemd-fstab-generator(8)