2 possible ways:
/forcefsck way for
# touch /forcefsck
and reboot. Next time the / will be fsck'ed .
Add these 2 kernel boot parameters:
What these 2 kernel parameters do:
KERNEL COMMAND LINE
systemd-fsck understands one kernel command line parameter:
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.
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
Reference: systemd-fsck-root manual