[OpenAFS] OpenAFS with RAID

Derek Atkins warlord@MIT.EDU
Wed, 28 Dec 2005 10:56:11 -0500

Quoting Paul Robins <paul@paulrobins.alldaypa.com>:

> Derek, if you're reading this, i've tried yanking a drive before and 
> the system doesn't crash, but any disk access hangs. I wish i could 
> spec a higher quality controller but i have a feeling it will be 
> rejected outright.

This test was done on a system that used software raid?  I'll admit that
my test was on a PATA system, not SATA system.  It was also a while ago,
on a 2.4 linux kernel (not 2.6).   You seriously can't add $20 to each
machine to get better controllers?

> If either of you could weigh in on AFS on top of DRBD i'd appreciate 
> it, I'm not fully up on whether a second server with an identical 
> filesystem could be made to take over a crashed AFS machine. I 
> appreciate all the help so far and wish there was a way i could 
> donate back.

I've never used DRBD in any form, so I don't have any experience.  All I CAN
say is repeat what has already been said:  The namei fileserver (which is all
you get on Linux) doesn't care what the underlying block device or filesystem
you use for /vicepx -- so if DRBD looks like any other disk/filesystem then
yes, AFS can be built on top of it.   Just make sure you never have the
same backend data served by two fileservers at the same time!

> Regards,
> Paul


       Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory
       Member, MIT Student Information Processing Board  (SIPB)
       URL: http://web.mit.edu/warlord/    PP-ASEL-IA     N1NWH
       warlord@MIT.EDU                        PGP key available