Basic listener query

Question

I have two Oracle Instance ORA1 and ORA2 running on Single Server SERVER1.
How do i configure listener on SERVER1 to listen on 1521 for ORA1 and 1522 for ORA2?

Answer 1

You can :
1. Have a single listener on a single port for all database instances
2. Two or more listeners, one for each port for each database instance
3. A single listener listening on multiple ports -- however, it would allow connections to the database instances on each of the ports (thus, if you have a single listener on 1521 and 1522 for database instances ORA1 and ORA2, it would allow connections to both instances on both ports)
This is how you could specify multiple ports for a single listener :
# LISTENER =
#  (ADDRESS_LIST=
#       (ADDRESS=(PROTOCOL=tcp)(HOST=hostname)(PORT=1521))
#       (ADDRESS=(PROTOCOL=tcp)(HOST=hostname)(PORT=1522))
#   )This is how you could specify separate listeners :
# LISTENER_1521 =
#  (ADDRESS_LIST=
#       (ADDRESS=(PROTOCOL=tcp)(HOST=hostname)(PORT=1521))
# LISTENER_1522 =
#  (ADDRESS_LIST=
#       (ADDRESS=(PROTOCOL=tcp)(HOST=hostname)(PORT=1522))
#   )The startup/shutdown/admin command would have to specify "LISTENER_1521" or "LISTENER_1522" for each listener.
What you choose to do depends on how you want to manage the environments.
For example, if you have a single listener for multiple databases, each running from a separate ORACLE_HOME and you have to apply a patch to the listener ORACLE_HOME that requires a listener shutdown, it would make the other databases inaccessible for that short time -- so you'd define another listener from another ORACLE_HOME while this listener is down for patching.
Hemant K Chitale
http://hemantoracledba.blogspot.com
Edited by: Hemant K Chitale on Oct 1, 2010 10:47 AM