Re: postgresql cluster on SAN

On 9/09/2010 11:02 AM, Lazaro Ruben Garcia Martinez 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. See:

http://wiki.postgresql.org/wiki/Shared_Storage

Setting it up isn't trivial and if you mess it up, you *WILL* get 
massive data corruption. If your shared storage dies, you still lose all 
your data.

Personally, I favour replication.

Anyway, added a reference to [[Shared_Storage]] for failover-only 
clustering to the faq entry posted earlier.


-- 
Craig Ringer

Tech-related writing at http://soapyfrogs.blogspot.com/