ext3 install problem

Forum: HD Install
Topic: ext3 install problem
started by: dysanf

Posted by dysanf on Feb. 08 2005,15:59

I just downloaded the latest version of dsl (dsl-0.9.3.iso) and installed it on an old compaq armada 7360DMT. During the install I chose the ext3 format option. Now when I boot I get the following error: mounting ext3 filesystem as ext2. When I check /proc/filesystems I don't see ext3 listed. Would someone please help me figure out what I am doing wrong with my install?

Thanks, and thanks for all the hard work on this great distro that truns old hardware into new agian :-)

dysanf

Posted by dysanf on Feb. 16 2005,19:25

I have done some more checking into this problem. It apears that ext3 support is written in as a module and not complied into the kernel. the module sits on an ext3 partition and has to be read first any Ideas on how to fix this or will there be another release soon that will fix the problem?

Thanks

Posted by AwPhuch on Feb. 17 2005,06:19

Too bad there isnt a script built in to activate the ext3 module after boot....once the system is running if ext3 is journaling then Im sure it would work on a reboot without problems

Brian
AwPhuch

Posted by AwPhuch on Mar. 02 2005,01:18

Please disreguard my last entry...apparently DSL and KNOPPIX doesnt support ext3, it MUST be compiled into the kernel...not as a module!

Quote

EXT3 Filesystem Upgrade

File systems such as ext3, reiserfs, etc are refered to as journalled file systems. Journaled filesystems are much quicker to recover after a machine crash than than thier non-journalled counterparts as it is not generally necessary to perform a complete "fsck" (file system check)which takes a consideruble amount of time on a large disk. The basic idea is that all updates to the file system are first written to a journal file before being written to the main file system. Each journalled filesystem has it supporters.

The one important thing to remember is that what ever file system you are using on your root partion must be compiled into the kernel; it cannot be a module! This is not 100% true since there are ways round it but you are asking for trouble if the kernel you are using can't read your root file system.

The ext3 file system is an extension of ext2, and it is easy to upgrade from ext2 to the ext3 (it is not possible to down grade explicitly, however, a partition using ext3 can be mounted and used as ext2 since ext3 is simply ext2 with a journal. Once this has been done however the journal is ruined since it is out of sync with the filesystem). First check that your kernel supports ext3 ("cat /proc/filesystems" will list the file systems supported by the kernel; and "lsmod" lists the modules loaded - if ext3 is one of them then do not upgrade your root (/) filesystem). Next run the command "tune2fs -j " to create the journal file. Then edit "/etc/fstab" and change the ext2 to ext3 for the device you have just changed. Finally try to "umount" and then "mount" that filesystem, if you can't "umount" then rebooting is easiest.

If you have installed everything under one partion then upgrading to ext3 is an all or nothing approach. If you have split the disk up into different partions (/, /usr, /home, ...) as I have then just pick one and try it out on that first.

Brian
AwPhuch

Posted by cbagger01 on Mar. 02 2005,04:33

If you want a journaling file system, use

Reiserfs 3.x

DSL / KNOPPIX has built in support and reiserfs is faster and more stable than ext3.

ext3 should be used if the user needs backwards compatibility to ext2 for certain utility programs (MSWindows linux FS readers, linux rescue floppys without reiserFS / EXT3 support etc).

I've used reiserfs on a Pentium 60Mhz and have noticed no peformance problems. I have not done a benchmark test, but this is just my subjective perception.