[Pacemaker] Getting Started

[Digimer]

On 12/03/2012 09:24 AM, Brett Maton wrote:
> Hi List,
> 
>   I'm new to corosync / pacemaker so please forgive my ignorance!
> 
>   I currently have Postgres streaming replication between node1(master) and node2(slave, hot standby), the replication user authenticates to master using an md5 password.
>   All good there...
> 
>   My goal use pacemaker / heartbeat to move VIP and promote node2 if node1 fails, without using drdb or pg-pool.
> 
>   What I'm having trouble with is finding resources for learning what I need to configure with regards to corosync / pacemaker to implement failover.  All of the guides I've found use DRDB and/or a much more robust network configuration.
> 
> I'm currently using CentOS 6.3 with PostgreSQL 9.2
> 
> corosync-1.4.1-7.el6_3.1.x86_64
> pacemaker-1.1.7-6.el6.x86_64
> 
> node1	192.168.0.1
> node2	192.168.0.2
> dbVIP	192.168.0.101
> 
> Any help and suggested reading appreciated.
> 
> Thanks in advance,
> Brett

Welcome to clustering!

I am not sure how postgres does it's hot-standby and data replication,
so allow me to speak generally.

The floating IP is trivial and it is the first example used in the
"Cluster From Scratch" tutorials. If you can "promote" the hot-standby
using '/etc/init.d/postgresql start', then you can easily have postgres
started/stopped by pacemaker to relocation of services. There might be a
postgresql specific resource agent which, if so, would likely provide
much more fine-grain control of postgres.

At this time, crmsh is the tool to use with CentOS 6, so look at the
latest crmsh cluster from scratch tutorial below:

http://clusterlabs.org/doc/

-- 
Digimer
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