systemd-fsck@.service, systemd-fsck-root.service, systemd-fsck — File system checker logic
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 only if the
root filesystem was not checked in the initramfs.
systemd-fsck@.service is used for all other
file systems and for the root file system in the initramfs.
These services are started at boot if
/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 on
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.). These checkers will decide if
the filesystem should actually be checked based on the time since
last check, number of mounts, unclean unmount, etc.
If a file system check fails for a service without
nofail, emergency mode is activated, by isolating
systemd-fsck understands these kernel
command line parameters:
One of "
the mode of operation. The default is "
and ensures that file system checks are done when the file
system checker deems them necessary. "
unconditionally results in full file system checks.
skip" skips any file system
One of "
no". Controls the
mode of operation. The default is "
and will automatically repair problems that can be safely
yes" will answer yes to all
questions by fsck and "
no" will answer no to