[Pacemaker] IP address for HA service

[Andrew Beekhof]

On Thu, Apr 14, 2011 at 6:39 PM, Carlos G Mendioroz <tron at huapi.ba.ar> wrote:
> Hi,
> I've a doubt on the best way (tm) to deal with HA in the case of services
> that are somehow proxies to some other resource (i.e.
> stateless in some sense).
>
> The problem seems to be that the clients need to know its identity
> and location, which usually boils down to IP address.
>
> Even though some services might run well with anycast models,
> many are TCP based so anycast does not fit that good.
>
> "moving" the IP address seems the usual mechanism that
> pacemaker based resources use. This implies that the service itself
> has to be restarted, because many depend on the service IP address
> being attached to the host for the configuration to be accepted.
>
> Has anybody thought about having a local (i.e. loppback) address
> and then switching ARP responsibility over the LAN as an alternative ?
> Has this been implemented already and I'm rediscovering a wheel ? :)

I think there's something like that in the IPaddr agent (for
ldirectord support IIRC)