I was having trouble with a 10g database today. I have the database working OK but the web console wasn’t working. It was saying that the database was down even though I knew it was up and working OK. I eventually noticed that it was using the wrong port number trying to talk to the listener. I don’t know how I managed that, but I did.
Anyway, I then had to try and work out how to change what port it was using. I found this web page Manually configure the Oracle 10g EM dbconsole that told me about the emca tool. I used that to reconfigure the setup and then it was fine.
The basics are this
#> emca -config dbcontrol db
STARTED EMCA at Fri May 14 10:43:22 MEST 2004
Enter the following information about the database
to be configured.
Listener port number: 1521
Database SID: AKI1
Service name: AKI1.WORLD
Email address for notification: martin dot zahn at akadia dot ch
Email gateway for notification: mailhost
Password for dbsnmp: xxxxxxx
Password for sysman: xxxxxxx
Password for sys: xxxxxxx
But check the page for more information and if you are still having trouble getting OEM to work then you might want to try reading document 278100.1 on MetaLink/My Oracle Support or logging a Service Request with Oracle.