Ubuntu: Turn off Periodic FSCK
I halt my computer at night, and boot it in the morning. This reduces my carbon impact. Alas, Ubuntu for whatever brain-dead reason doesn’t trust its filesystem. As if we lived in the 1970s it insists on checking the filesystem consistency every thirtieth boot. I sip my morning coffee, check my workstation, and have to hit ESC . . .
So, I googled a bit, and found a helpful forum thread. I thought I’d offer my own tiny variation:
0-09:57 dannhowa@T60p ~$ sudo tune2fs -c 0 `mount | awk '$3 == "/" {print $1}'`
tune2fs 1.40.8 (13-Mar-2008)
Setting maximal mount count to -1
Update: wamukota made an excellent suggestion, that one can instead set an interval with the -i flag. For example, one could set their computer to check every three months:
0-19:06 djh@noneedto ~$ sudo tune2fs -i 3m `mount | awk '$3 == "/" {print $1}'`
tune2fs 1.41.4 (27-Jan-2009)
Setting interval between checks to 7776000 seconds
Okay, that is a scary-looking command-line. Let me break it down. First, here are what filesystems we have mounted:
0-09:58 dannhowa@T60p ~$ mount /dev/sda3 on / type ext3 (rw,errors=remount-ro) proc on /proc type proc (rw,noexec,nosuid,nodev) /sys on /sys type sysfs (rw,noexec,nosuid,nodev) varrun on /var/run type tmpfs (rw,noexec,nosuid,nodev,mode=0755) varlock on /var/lock type tmpfs (rw,noexec,nosuid,nodev,mode=1777) udev on /dev type tmpfs (rw,mode=0755) devshm on /dev/shm type tmpfs (rw) devpts on /dev/pts type devpts (rw,gid=5,mode=620) lrm on /lib/modules/2.6.24-21-generic/volatile type tmpfs (rw) /dev/sda1 on /C type fuseblk (rw,nosuid,nodev,noatime,allow_other,default_permissions,blksize=4096) securityfs on /sys/kernel/security type securityfs (rw)
The command we really want to run turn off checking of / is:
sudo tune2fs -c 0 /dev/sda3
But everyone’s / is mounted somewhere different, based on what sort of disks you have and how they are partitioned. If you wanted to boil it down in to one command you have to pluck the name of the disk from the mount command, and for this, awk is the shizzle. For example, you could print the third word followed by the first word of each line this way:
0-10:05 dannhowa@T60p ~$ mount | awk '{print $3" "$1}'
/ /dev/sda3
/proc proc
/sys /sys
/var/run varrun
/var/lock varlock
/dev udev
/dev/shm devshm
/dev/pts devpts
/lib/modules/2.6.24-21-generic/volatile lrm
/C /dev/sda1
/sys/kernel/security securityfs
And add a dash of logic, if the third word is “/” then print the first word:
0-10:06 dannhowa@T60p ~$ mount | awk '$3 == "/" {print $1}'
/dev/sda3
And through the miracle of back-ticks:
0-10:07 dannhowa@T60p ~$ sudo tune2fs -c 0 `mount | awk '$3 == "/" {print $1}'`
tune2fs 1.40.8 (13-Mar-2008)
Setting maximal mount count to -1
Now, I am cocky and I maintain backups of important files. Before doing what dannyman dot told you dot com, you may wish to take a glance at the tune2fs man page:
OPTIONS
-c max-mount-counts
Adjust the number of mounts after which the filesystem will be
checked by e2fsck(8). If max-mount-counts is 0 or -1, the numâ€
ber of times the filesystem is mounted will be disregarded by
e2fsck(8) and the kernel.
Staggering the mount-counts at which filesystems are forcibly
checked will avoid all filesystems being checked at one time
when using journaled filesystems.
You should strongly consider the consequences of disabling
mount-count-dependent checking entirely. Bad disk drives,
cables, memory, and kernel bugs could all corrupt a filesystem
without marking the filesystem dirty or in error. If you are
using journaling on your filesystem, your filesystem will never
be marked dirty, so it will not normally be checked. A filesysâ€
tem error detected by the kernel will still force an fsck on the
next reboot, but it may already be too late to prevent data loss
at that point.
See also the -i option for time-dependent checking.
You might also experiment with a modern filesystem, by running FreeBSD or Solaris.
