My Switch Between EXT3 and REISERFS AND EXT3 AND......

This is a post about the recent FileSsytem crash I had, and to
give advices to future linux users if the question of which file system
to choose. I'm no kernel/FS hackers, but as a user, I have used pretty
much all major distros for the past 6 years (as my daily machine)
including source-based gentoo.

I have about 3-4 hundred gigs of space 70% used in my newly
purchased Dell machine (not my old overclocked dual procs
self-assembled bleeding edge hardware). And seeing the Fedora Core 5
just came out, have to try it out (I still think RHAT being the biggest
800lb Gorrilla is still in better position than others when fighting
the MSFT dinosaurs).

All the FileSystem (FS frm now on) are reiserfs 3 except /boot,
as I been using the reiserfs with noatime for past 2 years. It seems
fast, and comparatively safe (XFS/JFS).

Well, after the FC5 installation, I was going through the usual
getting-latest-kernel-compiling-modules-just-to-get-somethin-workin
routine. The machine hanged...hard. Well no problem it seemed, seeing
the hard drive was not being accessed, I promptly do a hard reset. Bad
idea,. After that, the next boot, the kernel tells me one of my biggest
logical reiserfs partition name MP3, it's "superblock" is missing /
corrupted, and would not go any further. Well, okay, dun panick. Grab
one of the live CD, take out the partition in fstab and reboot. Once go
in, reiserfsck the partition tells me I need to reiserfsck
--rebuild-sb.

Now at this point, I was just really pissed not just about the
situation, but about the lack of professionism for reiserfs. The Error
msg reiserfs team put in has the "give us $25 and we'll help you for 10
minutes" paragraph, as well as all the CREDITS. But it doesn't explain
clearly what the user to do at this point, and what are the other
options. If a user is Joe sixpack w/ no computer science background see
this, he would've backup whatever the data left, and take out the rusty
winxp cd for restall.

So I did the --rebuild-sb. Well it turns out it's a logical
partition within the extend one. And reiserfsck prompt you for lots
question including block size. I know the answer, but why can't a great
programmer who did this amazing (?!) fsck prog figure out the stupid
block size for the partition? I mean it's not hard....so at least scan
the partition and tell the user if he wants to select that.

After reiserfs --rebuild-sb, things sink even more, now the
superblock is still bad, and I can't even access the /dev/hdcx device.
At this point I googled pretty much for a whole day, and learn as much
as I can about reiserfs....it didn't help. So I ddrescue (it's a great
tool, you'd love it more than your gf when hdd crashes.) the whole
100gig partition to a image file. And then I mount it with losetup as a
loop drive, and try reiserfsck --rebuild-tree on it. Still wouldn't
work, Device doesn't exist. Well, then try zeroing out the partition
table and recreate it. w/ dd if=/dev/zero . Now reiserfsck prompts me
about superblock again. I tried --rebuild-sb again, --rebuild-tree. No
luck....the partition there, but I cannot touch it.

Couple of important things I realized,
1) reiserfs (version 3) IS NOT ATOMIC. What it means is it journal the
metadata portion, metadata is atomic, but not the data. So there is
still potential corruption when there are power outage or
user-stupidity. Daniel Robbin has some articles at ibm.com discussing
the FS type , yes the EXT3 could be slower, but it's journalling is for
data.
2) reiserfs has no tools to work with when it comes to recovery or
even just regular maintainance. reiserfsck ,......that it! Most of the
other great little tools out there either needs you to recompile the
apps w/ reiserfs support, or just flat out dun support it. And do you
know if you google "recover reiserfs partition", what u gonna get? A
commercial tools call "Kernel ReiserFS - Data Recovery Software", and
they charge $429 a license.
My data is important to me, and I think programmers deserved to be
paid. But the company seems detached from reality for charging 400+ for
a recover software when there are data recovery cmopany charge pretty
much the same amount for recovery work. If I'm at the mid to low end of
spectrum, I wouldn't pay 400+ for this software, 100-200 max, and if
I'm at the high end, I'll pay abit more and just ship it to the
recovery company to retrive all data. These guys don't have a clue
about pricing.
Anyway, I downloaded the demo, and as promise all my data is there.
it's just the superblock and the metadata are messed up. I googled
another 50 times for advices/tools, and I learned alot about system
recovery, partition tools,image files etc.etc. But none if them works
in this situation. And I'm not paying $500 for that software or a
recovery job.
I tried testdisk from CGSecurity, but no luck. But they have
another little tool PhotoRec. Don't let the name fool you, it does alot
more then Photo. It actually try and read every single block and match
the underlying pattern against it's predefined file header list. It
does not retain the file name, and you do get some false positive,
because it's so thorough. I ran it, got most of my media files back,
but in f1234.mp3 format. No matter, this is a lesson learned , and for
a price of having messed up file names. I'll gladlly pay it.
Once photorec's done retreiving my files, I rebooted back to my
linux box, another reiserfs superblock corrupted message popup during
fsck and wouldn't. I didn't snap, calmly I boot it in windows, open up
YAReG (the tool that let you read reiserfs from windows), copy all the
stuff to another FAT32 partition. Boot a livecd, fdisk delete the
partition.
Then I backup all the important data, and delete all the reiserfs
partition and reinstall the OS as EXT3. I will never use or recommand
reiserfs to another soul. And unless reiserfs4 is IN THE KERNEL TREE.
And all the ppl up there with Torvald approves it, I will not use it.
And not that I didn't want to pay $25 to Reiser & Co. But I just cannot
wait, and having a corrupted FS and a donation msg AT THE SAME TIME
feels like KIDNAPPING to me.

.

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