take care of the default listener definition

when you use the “listener.ora” to start the tnslsnr process,you must take care of the default listener definition.

If there is no content in listener.ora,but you want to start tnslsnr process using “static listener”.what will happen?

[oracle@dg1 admin]$ pwd

/opt/ora10g/product/10.2.0/db_1/network/admin

[oracle@dg1 admin]$ cat listener.ora

# listener.ora Network Configuration File: /opt/ora10g/product/10.2.0/db_1/network/admin/listener.ora

# Generated by Oracle configuration tools.

The listener.ora is empty.now I will execute command “lsnrctl start”

[oracle@dg1 admin]$ lsnrctl start

LSNRCTL for Linux: Version 10.2.0.4.0 - Production on 26-OCT-2010 21:45:24

Copyright (c) 1991, 2007, Oracle.  All rights reserved.

Starting /opt/ora10g/product/10.2.0/db_1/bin/tnslsnr: please wait...

TNSLSNR for Linux: Version 10.2.0.4.0 - Production

System parameter file is /opt/ora10g/product/10.2.0/db_1/network/admin/listener.ora

Log messages written to /opt/ora10g/product/10.2.0/db_1/network/log/listener.log

Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=dg1)(PORT=1521)))

Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))

STATUS of the LISTENER

------------------------

Alias                     LISTENER

Version                   TNSLSNR for Linux: Version 10.2.0.4.0 - Production

Start Date                26-OCT-2010 21:45:24

Uptime                    0 days 0 hr. 0 min. 0 sec

Trace Level               off

Security                  ON: Local OS Authentication

SNMP                      OFF

Listener Parameter File   /opt/ora10g/product/10.2.0/db_1/network/admin/listener.ora

Listener Log File         /opt/ora10g/product/10.2.0/db_1/network/log/listener.log

Listening Endpoints Summary...

  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=dg1)(PORT=1521)))

The listener supports no services

You see that it start the default listener.maybe it does not matter when you use single instance.but how about using rac?because of the crs_stat manage the listener which is defined  in the name of “listener_” in listener.ora,you must take care of it.

If you execute the command “lsnrctl start”,the default listener will run but not listener_.so, vip may be not used,and crs_stat –t will show that the listener is offline.