|Oracle® Enterprise Manager Cloud Control Upgrade Guide
12c Release 2 (188.8.131.52)
Before you deploy and configure Oracle Management Agents 12c (Management Agent) as described in Deploying and Configuring Oracle Management Agents, you must ensure that the old Management Agents remain in the same mode as they were before the Management Repository was backed up. In other words, if your old Management Agents were running in secure (or unsecure) mode before the Management Repository was backed up, then they must continue to run in the same mode while you deploy and configure the new Management Agents for them.
Do not resecure the Management Agents after backing up the Management Repository. If you do so, the ping test might fail while performing the healthcheck because of a mismatch between the configuration stored in the repository and the actual configuration of the Management Agent. You will see the following
KEY_MISMATCH error in the
gcagent.log:2011-09-28 05:41:46,192 [82:B5BF5C12:GC.Executor.1 (Ping OMS)] WARN - Received response status KEY_MISMATCH gcagent.log:2011-09-28 05:42:16,231 [89:D485F18E:GC.Executor.5 (Ping OMS)] WARN - Received response status KEY_MISMATCH gcagent.log:2011-09-28 05:42:29,232 [1:3305B9] WARN - Received response status KEY_MISMATCH
If you still want to resecure the Management Agents for some reason, then follow these steps:
Disable the health check by running the following SQL query against the old Management Repository.
BEGIN PRE_UPG_UTL.set_param('bypass_hc', '1'); END; / commit;
Switch over the Management Agent as described in Switching Over to Oracle Management Agent 12c.
Secure the new Management Agents.
$<AGENT_INSTANCE_DIR>/bin/emctl secure agent
Start the new Management Agents.
$<AGENT_INSTANCE_DIR>/bin/emctl start agent
Enable the health check.
BEGIN PRE_UPG_UTL.set_param('bypass_hc', '0'); END; / commit;