Tuesday, March 27, 2007
When we receive above error ... then first place to check tns_entry.
Are you able to connect "user/pwd@tns_entry".
SQL*Plus: Release 10.2.0.1.0 - Production on Tue Mar 27 10:46:05 2007
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SQL> conn system@db01
ORA-12154: TNS:could not resolve the connect identifier specified
Now i am troubleshoot ORA-12154 error and check my OEM status again.
SQL> conn system/oracle@db01
Location : $ORACLE_HOME/hostname.domainname_SID/sysman/log
You can also check "agent status"
Number of XML files pending upload : 0
Size of XML files pending upload(MB) : 0.00
Available disk space on upload filesystem : 18.61%
If number of XML files pending upload if greater than 0 then you should wait to load all pending files then try to change OEM status.
Note : May be more reason but i am face all this error so i share my exprience.