2

I've recently came across several servers with different "strategies" for their /boot partition (btw, always as /dev/sda1, 512M)

Some servers use ext2 for /boot, some use ext3 for /boot, and for the latter some have turned off journaling or turned off journaling and added the sync option. I won't take relatime and similar in account since I don't believe those atime options are relevant here.

  • Are there any important and relevant differences between an ext2 partition and a ext3 partition with journaling turned off for a /boot partition? I believe that online file system growth and htrees have no use at all for a /boot partition and I don't see what else ext3 offers over ext2.

  • Would "sync" option be recommended if there is no journaling?

  • Does any of these setups stand out from the rest in terms of easy of administration in case of crash/panic/oops or performance wise?

  • Is there any general consensus on the partition/format type for such a small (512MB) /boot partition should be?

3

From a functional standpoint, ext3 is ext2 + journaling.
Using ext3 without journaling means to use an ext2 filesystem, but with a more recent code base (ext3's one).

However, there is not reason why you can't use ext4 as a boot partition, as Grub supports it since years.

The 512 MB limit for a boot partition is a vestige of some very old BIOS which can not boot from a partition larger the 512 MB. You can not use whichever size you want for your boot partition, but anything over 512-1024 MB is overkill.

3
  • 1
    Note: recent (2014+, I think) kernels use the same "ext4" code to access ext2/3/4 partitions, since the backward compatibility is excellent. Specifying ext2/ext3/ext4 only toggles default functionality bits (and what mount options you can/cannot request explicitly). – Piskvor left the building Jan 12 '16 at 10:02
  • @Piskvor Thanks for the info. I haven't gone in the kernel source for a while, I guess I'm going to check the info you just gave me. – BlakBat Jan 12 '16 at 10:20
  • @BlakBat: Based off Linux Kernel News, I didn't bother to go all the way ad fontes (although links were provided :)). – Piskvor left the building Jan 12 '16 at 10:26

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.