topic Re: Changing back to ext2 from ext3! in Operating System - Linux

Changing back to ext2 from ext3!

Jagadesh — Tue, 02 Sep 2003 08:32:52 GMT

I have installed RedHat advanced server in ext3 fs. I want to change the ext3 to ext2 fs now. How can the same be changed.

Thanks in advance
Jagadesh

Re: Changing back to ext2 from ext3!

Mark Grant — Tue, 02 Sep 2003 09:14:49 GMT

Just change the filesystem type in /etc/fstab from ext3 to ext2.

ext3 is only ext2 with journaling and if the system thinks it is a ext2 it will mount it as such.

If you want to do it properly though so the journal inode is actually removed then

tune2fs -O ^has_journal {disk device}
e2fsck {disk device}

Then change /etc/fstab

Re: Changing back to ext2 from ext3!

Jerome Henry — Tue, 02 Sep 2003 10:12:42 GMT

Nevertheless,

ext3 is a great improvement on ext2, journalization allows several things, such as clean reboot after sudden power failure, and so on...

I would advise to go back to ext2 only if you have programs unable to deal with ext3... But I'm sure you have a good reason to wish this change.

J

Re: Changing back to ext2 from ext3!

Balaji N — Tue, 02 Sep 2003 12:23:35 GMT

hmm. before that can i ask one question. why is that the you want to goback to ext2.

is there a specific reason. ext3 is considered superior in performance and reliability over ext2.

-balaji

Re: Changing back to ext2 from ext3!

Mark Grant — Tue, 02 Sep 2003 13:13:25 GMT

Balaji,

Not so sure ext3 has superior performance over ext2 particularly on SMP systems. Admittedly I'd always prefer a journaling file system myself but some software doesn't support it e.g Omniback 3.5

Regards.

Re: Changing back to ext2 from ext3!

Balaji N — Tue, 02 Sep 2003 16:04:05 GMT

hmm....

having said that was wondering if i could find some data to validate my point. still looking around.

i know that ext3 could be a bit slower having the need to write the journal.

but still looking. anybody has some data for comparisons. i had one but unable to locate.

thanks for pointing out.

-balaji

Re: Changing back to ext2 from ext3!

Steven E. Protter — Tue, 02 Sep 2003 16:25:23 GMT

If this is a theoretical excercize, you can remove the filesystem with linixconf and rebuild it with ext2.

I know of know conversion utility.

I also know of know reason to do this. ext3 is an improvement over ext2 and has virtually the same feature set plus some enhancements.

Not having a convincing reason to make the change, I would not do so.

SEP

Re: Changing back to ext2 from ext3!

John Meissner — Tue, 02 Sep 2003 17:41:06 GMT

I completely agree with SEP - ext3 is SOOOOO much better than ext2 - It allows for recovery in the event of a crash and is much more forgiving. to revert to an earlier file system type (ext2) would make no sence except in theory to see if you can do it. (but why would you want to?)

Re: Changing back to ext2 from ext3!

Caesar_3 — Tue, 02 Sep 2003 18:47:38 GMT

Hello!

Read this : http://linux-sxs.org/pipermail/linux-users/2003-February/014488.html

You will get the commands flow,
but better is to use the ext3 than ext2
so check it again.

Caesar