Hi Dejan, On 04.04.2012 17:56, Dejan Muhamedagic wrote: > The timeout is a timeout, wherever it happens.
Unfortunately not! If the monitor operation times out and Pacemaker moves on, the wget process (and thus the whole monitor process) will keep running. In fact, it may still be running many minutes after the timeout happened. And since the monitor (at least in case of the apache resource agent) can't be run twice in parallel, this effectively prevents further monitor operations until wget has timed out. And that's exactly where we get a problem. > So, you want the resource agent to notice while running monitor > that it can now talk to the server? Yes, I want automatic recovery. The resource agent should notice when apache is back and working again. And that works fine with a patched apache resource agent. >> On a side note: >> The apache resource agent allows to supply a config file, where one can >> override the parameters for curl/wget. But the implementation here is >> bogus, because even if you supply this file, it always does a default >> test with default parameters first, so this is useless in this case... >> (I consider this behavior to be a bug). > If you use a config test file, you'd need to define a monitor > with depth 10. The depth 0 monitor (default) is always testing > the statusurl. Yes, I figured that, but it's besides the point. If I use depth 10, it will first do the simple (depth 0) test anyway (!), and after that the advanced (depth 10) test. And since the simple test doesn't have a useful timeout for wget, it will still stall for a long time if apache doesn't respond, and it is irrelevant what the advanced test does. @simple tests: Even though we run a complex web application behind apache (apache acts as a load balancer using mod_jk), I don't want a more complex test than fetching /server-status on localhost. This simple test already shows that apache is working and has threads available for clients to connect. Failover for our application servers is done by mod_jk, I don't need Heardbeat/Pacemaker for that. Think of it as independent failover at each layer: Virtual IPs with Heartbeat/Pacemaker for failover between Apaches, mod_jk for failover between Tomcats, mmm_monitor for failover between MySQL servers. Best regards, David _______________________________________________ Linux-HA mailing list [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
