On Mon, Dec 27, 2010 at 12:29:10PM +0100, alexander.kra...@basf.com wrote: > > Hi, > > > > I was recently reviewing some logs of a SAP HA installation and > > found out that SAPInstance tries to start the service in the > > monitor action. That includes probes too. Further, if it finds a > > different instance running it stops it. Is it possible that more > > than one SAP instance runs on a host? No SAP expert here :) > > Yes, this is correct. But you have to distinguish between the > SAP instance and the sapstartsrv process. What the function > check_sapstartsrv does is to control the sapstartsrv process > only, which is not the SAP instance. This process runs as a > daemon and implements the required functions "start, stop, > monitor". So the SAPInstance RA is in reality only a interface > from the resource manager to this sapstartsrv daemon. > It was the initial design idea for this RA, not to (re-)implement > all the required knowledge to handle the real SAP instance > with all it flavors and different releases. This is mainly to > avoid constant changes to the RA. > > Why is the sapstartsrv also stopped in the check_sapstartsrv > function ? > This is because in early releases on the SAP Enqueue Replication > Server (that is what the master/slave stuff is for) those two > instances did run with the same instance number (tcp/ip ports). > So after a failover the RA did need to make sure that the right > instance of the daemon is running. In fact today this coding > should not be needed anymore, except someone still runs such > a type of installation, or someone startet a wrong daemon > manually. So I would leave it in, because it doesn't hurt and > ensures that we always operate on the instance we intend to.
With the latest series of patches, the sapstartsrv is not started unless there are some SAP processes found. That's fine with me. Thanks, Dejan > > Thanks, > > > > Dejan > > Regards > Alex > _______________________________________________________ > Linux-HA-Dev: Linux-HA-Dev@lists.linux-ha.org > http://lists.linux-ha.org/mailman/listinfo/linux-ha-dev > Home Page: http://linux-ha.org/ _______________________________________________________ Linux-HA-Dev: Linux-HA-Dev@lists.linux-ha.org http://lists.linux-ha.org/mailman/listinfo/linux-ha-dev Home Page: http://linux-ha.org/
