On Wed, 14 Jul 2010, Jonathan Nilsson wrote:
I would like to replicate home directories (and other AFS volumes that are
primarily
accessed read/write) for the purpose of faster disaster recovery in certain
common cases,
such as local hardware failure on an AFS File Server. I am planning to do this
by always
mounting these volumes with the "-rw" flag, then simply adding a replication
site, and
running a script that will "vos release" all these volumes every so often.
We don't do this for homes, but we do it for auxiliary data volumes (100GB
and up), which we don't usually send to our tape backup system. The
normal user access path is via explicit RW mount, and we mount the
RO replicate, as well as yesterday's .backup, under well defined paths so
that the users can dig into them if they feel the need.
What I wish we had is a -dryrun and -showfiles flag for vos release, so I
can see what files would be copied and how big they are, before I do the
copy. I auto-release several TB of data daily and with my normal user
activity, it only takes 15-30 mins for the incremental releases, but
occasionally much longer. I wish we had those options available to
incremental 'vos dump' too.
We have separate management tools (currently clunky) to make sure that the
replicates are on a different server, in a different machine room, but
that side of things is far from perfect yet. We don't have the server
space to allocate a RO partition to match each RW partition, so stuff is
mixed up.
I'm still trying to figure out how to make more copies available using
shadow and clone volumes, but for a single replicate, the mature RO
replicate and 'vos release' works great.
Richard
--
Richard Brittain, Research Computing Group,
Kiewit Computing Services, 6224 Baker/Berry Library
Dartmouth College, Hanover NH 03755
[email protected] 6-2085
