Re: postgresql cluster on SAN

On Wed, Sep 8, 2010 at 9:02 PM, Lazaro Ruben Garcia Martinez
<lgarciam(at)estudiantes(dot)uci(dot)cu> wrote:
> Thank you very much for your answer, In the cluster that i said before I
> need only failover.
> In the documentation of postgresql I read about the Shared Disk Failover,
> this tecnique avoids synchronization overhead by having only one copy of the
> database. It uses a single disk array that is shared by multiple servers. If
> the main database server fails, the standby server is able to mount and
> start the database as though it was recovering from a database crash. This
> allows rapid failover with no data loss. One disadvantage is that the
> standby server should never access the shared storage while the primary
> server is running.
>
> For these resons is posible to use a SAN?

Yes, however, a SAN is not a replacement for some kind of streaming
replication in case you need to recover a database to a previous
uncorrupted state or should the SAN fail in some catastrophic way.
You need to look up "fencing" for your servers.

--
To understand recursion, one must first understand recursion.