On Fri, Jun 20, 2008 at 12:35, Michael Alger <[EMAIL PROTECTED]> wrote: > The question in brief: > > Is it possible to configure heartbeat such that a managed resource > (an IPaddr) is affected by the status of an unmanaged resource?
yes - this was the original purpose of "unmanaged". although i think that we don't start monitors for unmanaged resources (which if true, would be a bug) > > In theory I could possibly set up a process outside of heartbeat > that periodically checks the status of the service in question, > and updates an attribute in the CIB. I can then add a constraint > which makes it "highly undesirable" for the IPaddr to be placed on > a node where the service in question is broken. Is this the best > way of going about this? > > > The question in full: > > I've got a working squid + IPaddr setup with heartbeat 2.1.3 in > a two node cluster. > > There are IP addresses bound to the loopback interface on both nodes > which squid listens on, and which the firewall forwards connections > to. The firewall routes the subnet these addresses live on to the IP > address managed by heartbeat, so whichever node has the magic IP is > the currently active proxy. > > With the current setup, squid is managed by heartbeat, which means > it stops it running on the inactive node. This results in a delay of > a few seconds if the currently active node changes, as heartbeat > first moves the IP address, then stops squid on the old host, and > starts it on the new one. > > I would like to avoid this delay, as it's not actually necessary for > squid to be stopped on the inactive node. However, I do want > heartbeat to monitor whether squid is running on a node so it can > avoid moving the IP address to a node which isn't actually running > squid. Squid itself has crash recovery, so it's unlikely heartbeat > will be able to get it running again just by running the startup > script for it. > > I've looked at the "is_managed" attribute, but it appears setting a > resource to unmanaged prevents any actions, including monitor, from > being performed on it. Actually, it seems to check the status at > startup, but never again. > > Is there any way of configuring HA so that it will periodically > check the status of squid on all nodes (regardless of whether the > node is currently holding the IPaddr resource), so that I can use > squid's status as an input to resource constraints? > > Or, am I completely insane to want to do this in the first place? > My reasoning is that squid will be running on both nodes at all > times, unless there's something horribly wrong or the administrator > has decided to stop it for some reason. Therefore, it will probably > just create confusion if heartbeat takes it upon itself to start and > stop squid. In addition, I would prefer to minimise downtime, and > since there's no harm in having squid running on an inactive node > this seems an easy way to shave a few seconds off of the failover > delay. > _______________________________________________ > Linux-HA mailing list > [email protected] > http://lists.linux-ha.org/mailman/listinfo/linux-ha > See also: http://linux-ha.org/ReportingProblems > _______________________________________________ Linux-HA mailing list [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
