[Pacemaker] "cluster partitioning"?

[Andrew Beekhof]

On Sat, Jun 4, 2011 at 11:51 PM, Tomasz Chmielewski <mangoo at wpkg.org> wrote:
> Not sure if "cluster partitioning" is the right description here, so I'll
> try to explain what I want to achieve.
>
> Right now, I have 4 web/application servers, with heartbeat/pacemaker
> assigning IPs:
>
>
> (web1) - (web2) - (web3) - (web4)
>
>
> There is also a "mysql1" server, used by the webservers, which does not have
> heartbeat installed.
>
>
> "mysql1" server will be a master-master setup, with "mysql1" being accessed
> by the webservers, and the other mysql server as a failover.
> What I'd like to do, is "web4" being the "failover mysql server" - so the
> whole cluster would look like below:
>
>
>                            /web4) - (mysql1)
> (web1) - (web2) - (web3) - (web4/
>
>
> Now, if mysql1 dies, I would like one if it's IP addresses (used for MySQL)
> be assigned to web4, and only to web4.
> mysql1 should never have web* server IP addresses assigned (except the one
> used for MySQL, allowed to be moved to web4, and only to web4).
>
>
> Can I do it with heartbeat/pacemaker? If so, how?

Put them all in the same (6-node) cluster and use location constraints
to prevent the web servers from running on the mysql nodes and
vice-versa.