I am completely puzzled by this one and am hoping I can explain the problem clearly.
I have upgraded our 11g OEM to OEM 12c Cloud Control using the two system method. I am now in the process of deploying/configuring the 12c agents. I have deployed and configured the agent to one server running Oracle 10.2.0.4.0 (this may be part of the problem) and completed the switch to the 12c agent. I go into the 12c console, look for database targets on this server and the status is up. I then drill down to the database and an informational message is displayed saying -
IO Error: The Network Adapter could not establish the connection
The Connect Descriptor was (DESCRIPTION=(ADDRESS_LIST = (ADDRESS=(PROTOCOL=tcp)(HOST=tachi.ucdavis.edu)(PORT=1521)))(CONNECT_DATA=(SID=ars)(SERVER=DEDICATED)))
The summary field displays the message -
Agent is unable to communicate with the OMS. (REASON = Agent is Unreachable (REASON : Agent to OMS Communication is brokenFailure connecting to https://ares.ucdavis.edu:1159/em/upload , err -32 ).
The first thing I don't understand is the OMS it appears to be pointing to is on host ARES. Host ARES is the 11g OMS server, not the 12c OMS and I don't understand why it is trying to communicate with ARES. CLearly something has not been switched and I don't know what.
I have tried a couple of things on the 12c OMS server and am not sure if they are related. From the 12c OMS server I tried to telnet to tachi (the target host) on port 1521 and it fails. This is a firewall issue and so I don't know if opening port 1521 on the firewall on the target host (tachi) is what is causing the problem, I suspect it is as that is the case on the 11g OMS server, it can connect to tachi on port 1521.
I have searched and found references to this problem on Metalink and bug reports but supposedly this has been fixed.
Suggestions greatly appreciated.
Thank you. I am available this morning until 1:15pst and anytime tomorrow morning after 9:00am pst. I have asked the system administrator to open port 1521 on the target and when that happens I will test again.