[OpenAFS] OpenAFS with RAID

zeroguy zeroguy@verizon.net
Fri, 30 Dec 2005 21:55:22 -0500


On Fri, 30 Dec 2005 21:10:16 -0500
Jeffrey Hutzelman <jhutz@cmu.edu> wrote:

> On Wednesday, December 28, 2005 03:58:19 PM +0100 Horst Birthelmer 
> <horst@riback.net> wrote:
> >>
> >> Has anyone tried to run AFS on top of drdb (http://www.drbd.org/)?
> >> It seems to me that AFS would be unaware that it was running with
> >> a network distributed redundant block device under the /vicepx
> >> filesystems.
> >
> > The namei fileserver is unaware of the file system and device it's
> > running on.
> 
> True.  However, you cannot run multiple fileservers backed by the
_same_ 
> filesystem at the same time -- the AFS fileserver stores large amounts
of 
> state in-core, and having two fileservers running against the same
vice 
> partition at the same time would be a sure way to trash the contents
of 
> that partition.

In the case of DRBD, though, only one fileserver would be accessing the
partition at one time. In fact, it's impossible to read DRBD data from
more than one node at a time (at least with 2.6 kernels, and it's not
advised to do so with 2.4 kernels). I'm assuming you would mount a
/vicepX partition on the secondary fileserver, and restart the
fileserver process, in the case of a failure.

	-zeroguy