[OpenAFS] will OpenAFS serve my needs?

F. Even openafslists@elitists.org
Sun, 30 Mar 2008 19:49:33 -0500

On Sun, Mar 30, 2008 at 4:54 PM, Christopher D. Clausen
<cclausen@acm.org> wrote:
> F. Even <openafslists@elitists.org> wrote:
>  > On Sun, Mar 30, 2008 at 4:15 PM, Christopher D. Clausen
>  > <cclausen@acm.org> wrote:
> >>  Some sites actually still use a TSM client for native AFS backups.
>  >>  The older TSM 5.1r17 or 5.1r18 client still supports AFS "buta"
>  >>  file level backups.  Although you have to run the TSM backups from
>  >>  an AIX client machine.
>  >
>  > That shouldn't be an issue.  As of right now all the servers in the
>  > environment are AIX which are clients to AIX TSM servers.  But
>  > yes...some method of reliable and replicatable backup is necessary.
>  > Business continuity/disaster recovery needs to be a consideration
>  > also.
>  You might want to read this thread:
>  http://www.openafs.org/pipermail/openafs-info/2005-September/019570.html
>  Some sites are using AFS backup volumes (BK) for the case when a user
>  deletes a file.  These volumes are a Copy-on-Write snapshot of a volume
>  at a certain point in time (usually run at night.)  End-users can
>  directly access backup volumes and can generally copy the files out
>  themselves to restore accidentally deleted files.  There is only one
>  backup replica per volume though.
>  There are other methods of doing DR / BC instead of restoring from
>  backups.  There are ways to create volume replicas or copies and simply
>  point clients at a different server if something catches on fire and
>  burns to the ground.
>  In backup industry jargon, what are your Recovery Time Objective (RTO)
>  and Recovery Point Objective (RPO)?
>  http://en.wikipedia.org/wiki/Recovery_Point_Objective
>  http://en.wikipedia.org/wiki/Recovery_Time_Objective
>  Of course, a more traditional backup method for restoring files that are
>  no longer in the backup volume are probably wise.

Basically 24 hours.  All data is on SAN with some redundancy built in
there, along with complete daily backups of data and weekly backups of
the operating systems (which most recent version of is kept online for
immediate restore, all other versions are backed up to TSM with a
30-90 day retention depending).

Everything ends up in TSM if it's important data.  If it can't be
stored in TSM...it's not considered "backed up."  So...some method of
putting it in TSM is absolutely required.

So...if a server tanks...say an AIX box...if I re-import my VG's...how
do I go about restoring the AFS structure?  Can the metadata be dumped
separately?  Is it fairly non-trivial (scriptable at least) to
recreate the AFS structure and restore data back into that structure
(I would be keeping in mind that most of our data will probably
already be geographically redundant in a scenario such as this...but
regardless....this is something that would need to be possible).