2

Default Raspbian has the following details in /etc/fstab

proc            /proc           proc    defaults          0       0
/dev/mmcblk0p1  /boot           vfat    defaults          0       0
/dev/mmcblk0p2  /               ext4    defaults,noatime  0       0

The final column is

used by fsck to decide which order filesystems are to be checked. Possible entries are 0, 1 and 2. The root file system should have the highest priority 1 (unless its type is btrfs, in which case this field should be 0) - all other file systems you want to have checked should have a 2. File systems with a value 0 will not be checked by the fsck utility.

Hence, none of these partitions are being checked by fsck. Why would we not want that by default?

3

Typical usage of a Raspberry Pi is that it often gets rebooted. Every Linux filesystem has a mount counter and after X reboots, it will get checked with fsck. Unless you tell Linux not to do that, by way of fstab.

fsck is also rather slow on an SD card, and the Raspberry Pi isn't exactly the fastest horse on the race track. If they didn't do this, you would be asking "why is my RasPi so slow to boot every X times?"

If you want to find out the mount timer, issue this command:

sudo tune2fs -l /dev/mmcblk0p2 | grep mount

Will output something like

Mount count: 2
Maximum mount count: 25

You can also disable this with

sudo tune2fs -c 0 /dev/mmcblk0p2

but somehow just changing a value in a config file (/etc/fstab) and leaving the partition defaults as they are, seems more obvious to me.

  • 1
    Nice answer. In my case, I use it as a server, and hardly ever reboot. Thanks for the info. – Sparhawk Jun 18 '14 at 12:43

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