Hi there,
I'm currently in the process of deploying an 11gR2 Active Data Guard configuration with one master and two physical standby slaves and Fast-Start Failover for a Java JDBC application. Each instance has one read-only service that's always active and one read-write service that's only activated on the master:
srvctl add service -d smsgsig1 -s smsgro -l PRIMARY,PHYSICAL_STANDBY -e NONE -m NONE
srvctl add service -d smsgsig1 -s smsgrw -l PRIMARY -e SELECT -m BASIC -w 10 -z 150
Initially I planned to use the Oracle Notification Service (ONS) to notify the application in case of a change of master, which works, however after doing some testing it seems that simply letting the application retry enough times in case of a connection failure is sufficient to have it reconnect to the new master eventually, and complete any pending transaction.
So my question is: since I don't plan to use ONS anymore, do I need the Grid infrastructure and Oracle Restart at all to deploy Active Data Guard? The documentation does not seem to require it explicitly and all necessary tools, including srvctl, exist in the plain 11gR2 home. However is the service activation/deactivation mechanism going to work without Restart? To be honest I don't think it would but as this would simplify the deployment quite a bit I thought it would be worth asking :-)
Thanks for your insight,
Chris