systemd-fsck@.service, systemd-fsck-root.service, systemd-fsck — File system checker logic
systemd-fsck@.service
systemd-fsck-root.service
/usr/lib/systemd/systemd-fsck
systemd-fsck@.service
and
systemd-fsck-root.service
are
services responsible for file system checks. They are
instantiated for each device that is configured for
file system checking.
systemd-fsck-root.service
is
responsible for file system checks on the root file
system, but in only if the root filesystem wasn't
checked in the initramfs.
systemd-fsck@.service
is used for
all other file systems and for the root file system in
the initramfs.
Those services are started at boot if
passno
in
/etc/fstab
for the file system is
set to a value greater than zero. The file system
check for root is performed before the other file
systems. Other file systems may be checked in
parallel, except when they are one the same rotating
disk.
systemd-fsck
does not know
any details about specific filesystems, and simply
executes file system checkers specific to each
filesystem type (/sbin/fsck.*
).
This helper will decide if the filesystem should
actually be checked based on the time since last
check, number of mounts, unclean unmount, etc.
systemd-fsck
will forward
file system checking progress to the console. If a
file system check fails for a service without
nofail
, emergency mode is activated,
by isolating to
emergency.target
.
systemd-fsck
understands
one kernel command line parameter:
fsck.mode=
¶One of
"auto
",
"force
",
"skip
". Controls the
mode of operation. The default is
"auto
", and ensures
that file system checks are done when
the file system checker deems them
necessary. "force
"
unconditionally results in full file
system checks. "skip
"
skips any file system
checks.
fsck.repair=
¶One of
"preen
",
"yes
",
"no
". Controls the
mode of operation. The default is "
preen
", and will automatically repair
problems that can be safely fixed. "yes
" will answer yes to all questions by
fsck and "no
" will answer no to
all questions.