Re: Replication/Failover/HA solution

Ragnar Kjørstad wrote:

>On Mon, Jul 21, 2003 at 06:11:15PM -0400, Renney Thomas wrote:
>
>
>>I am having a hard time selecting a Replication/Failover/HA solution for
>>PGSQL. What is troubling is the number of solutions available in various
>>states of development. Does the fact that dbmirror and rserv appear in
>>the contrib directory, mean that they should be looked upon with more
>>legitimacy? Any suggestions?
>>
>>
>
>One possibility is to run postgresql (regular postgresql - no patches
>required) controlled by heartbeat (http://www.linux-ha.org/) on two
>nodes. Heartbeat will then make sure that only one of the nodes are
>active at any time.
>
>You will have to put the databases on shared storage; either something
>like a shared SCSI RAID, or a software replication device like drdb or
>md+nbd.
>
>
Another possibility (which I have not yet tested, but it was mentioned
in many Magazine Articles
(Linux Magazine, the German iX) is DRBD.
This Tool creates a RAID which is Shared betwenn 2 Nodes.
One Node is the Master and the Other is the Slave (and failover Node).
The Master writes data locally and sends the data over to the slave.
There are 3 Modes of Operation, A with highest Troughput but least
trust, B with Medium Troughput,
but Acceptable trust, and C with lowest (but still ok) troughput and
highest trust.

Just check it out here:

http://www.complang.tuwien.ac.at/reisner/drbd/

Regards,
Dani