Database Reference
In-Depth Information
4.
Reconfigure user-defined metrics if necessary.
5.
Verify the status of the agent.
emctl status agent
emctl upload agent
Switchover and Failover
Both the management service and repository can be switched over and failed over independently when using
level 2, 3, or 4 high-availability configurations. Switchover is usually done during planned maintenance, including
operating system and software patching, while a failover normally occurs during unplanned maintenance such as
hardware or software failure.
In a level 2 configuration, the switchover and failover of the management service follow the same procedure. As
mentioned earlier, this requires relocating the OMS virtual hostname and VIP to another host and then starting the
OMS manually or using Clusterware to automate the relocation. In level 2, 3, or 4 configurations that utilize a physical
standby database for the Enterprise Manager repository, the database has to be switched over (planned) or failed over
(unplanned). The OMS does not require any action in level 3 high availability because multiple management services
are involved. The SLB will monitor the management services and detect when one has failed and route traffic to the
available OMS.
To switch over the management repository using Data Guard, use the
DGMRL
command-line utility as the
Enterprise Manager console will not be able to switch over the repository. Follow these steps to do a switchover of the
management repository with a management service that has not been switched over:
1.
From the Enterprise console, choose Availability รค Data Guard Administration.
2.
Check that the Redo Apply process is up-to-date. Verify the ApplyLag status is zero as
shown in Figure
13-35
.
Figure 13-35.
Data Guard administration showing ApplyLag and TransportLag status