We are upgrading 10.2.0.4 enterprise edition single instance to 126.96.36.199 enterprise edition single edition manually. What should the listener status while doing upgradation. This is my first upgradation project. Please suggest.
Normally when you do an upgradation, the database services needs to be down with only the database being opened with the option "startup upgrade".
The listener on the database server to be upgraded needs to be down. Make sure you take the backup of the listener.ora and the tnsnames.ora file located in the 10g Home and once when you plan up to delete this home after the database is upgraded to 11g, you have a new listener created with the 11g Home
In that case, you can have the listener up, perform the upgrade (by starting the database in upgrade mode "startup upgrade") and once done, you can either drop the listener on 10g Home (if you have plans to delete the 10g Home) and cretae a new listener through 11g home.