Today, when I was trying to connect to the OEM Grid Control, I got “Login operation failed” error

The first file to be checked are the log and trace files at  Grid side. So I checked emoms.trc and emoms.log files under $OMS_HOME/sysman/log and didn’t find anything. I checked the repository database, it was up and running. After a while I realized that it’s a connection problem and checked $OMS_HOME/sysman/config/emoms.properties file and saw that it is trying to connect to the 2222 port  as a Repository Connection:

[php]oracle.sysman.eml.mntr.emdRepConnectDescriptor=(DESCRIPTION\=(ADDRESS_LIST\=(ADDRESS\=(PROTOCOL\=TCP)(HOST\=host03)(PORT\=2222)))( CONNECT_DATA\=(SID\=oemgrid)))[/php]

When I checked listener at the repository side, I saw that it wasn’t configured to accept connections from port 2222

I added the above port number to the non-default connection section at listener.ora file and started the listener

[php]second_listener =

(DESCRIPTION=

(ADDRESS_LIST=

(ADDRESS=(PROTOCOL=tcp)(HOST=host3)(PORT=2222))))

SID_LIST_second_listener =

(SID_LIST=

(SID_DESC=

(GLOBAL_DBNAME=oemgrid)

(ORACLE_HOME=/u01/oracle/product/10.2.0/db_1)

(SID_NAME=oemgrid)))

-bash-3.2$ lsnrctl  start second_listener
Listener Log File         /u01/oracle/product/10.2.0/db_1/network/log/second_listener.log
Listening Endpoints Summary…  
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=host3)(PORT=2222)))
Services Summary…
Service "oemgrid" has 1 instance(s).  
Instance "oemgrid", status UNKNOWN, has 1 handler(s) for this service…
The command completed successfully

[/php]

I tried to connect to the Grid Control again, and succeeded. So if you got “Login operation failed” error and didn’t get any information from the Grid Control log files, the listener and port issues can be the reason