On Fri, Aug 01, 2008 at 10:09:13AM -0500, Angel Rengifo Cancino wrote: > mmm, this is a different question: Do I really need to start/stop > services with haresources? Why can't I just simply mantain my > services always running (chkconfig services on)? Is it not enough > to change the IP alias between nodes?
That depends on your setup and what you want to achieve. The main issue then is how you decide which node in your cluster has the IP alias which makes it the "active" node, since heartbeat has no idea whether or not your important services are running (and working). Our squid is a reverse proxy for our websites, and we have two nodes running for availability. The active node is determined by whichever has a magical IP alias, which is managed by heartbeat. So heartbeat provides the basic failover logic, taking over if the other server is completely dead, etc. On top of that I have another script which continually polls our sites via the local squid instance, and updates a score in the CIB based on the results. This score affects placement of the IP address. Ideally this part of it would have been implemented in a similar fashion to pingd, but I wouldn't know where to even start such a thing. It's a bit crude, but it works. The main problem is that if the monitoring script stops, heartbeat has no idea and therefore can't factor that into its decision-making process. I haven't determined whether we can somehow store a "last updated" timestamp in the CIB and make heartbeat pretend the score is 0 if it's not reasonably recent; mostly because we haven't had a problem with the script stopping unexpectedly. _______________________________________________ Linux-HA mailing list [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
