Re: Oracle VMWARE aware?

lambu999_at_yahoo.com wrote:

> The case of one listener for multiple Oracle instances in different ver
> of oracle: Do we copy one specific listener.ora file to some common
> directory and make all the modifications there and then set the
> TNS_ADMIN env variable? Is that enough or do we need to do anything
> more ? Does it apply to sqlnet.ora and tnsnames.ora? (can someone
> please suggest a book/manual for learning more)
>
> Thanks.
>

Here's a start:

For each ORACLE_HOME on your machine, there is an $ORACLE_HOME/network/admin directory. Choose the newest (highest) version of Oracle and start the listener from that ORACLE_HOME. In the simplest case, all running instances of Oracle should auto-register with that listener (new feature ever since version 8i). When an instance starts up, it tries to auto-register, if the listener isn't yet running, it tries again every 1 to 10 minutes or so (PMON), so be patient if you start the listener after the database instead of before. You can see this happen in the listener.log file, look for a "service register" entry. "lsnrctl services" command will show you the services currently registered and being listened for.

If you have an older version, such as 8.0.6, or for some other reason need to explicitly register the instance, such as for use by a db_snmp agent for Enterprise Manager, you can add the following type of entry in listener.ora, this example has two instances in different ORACLE_HOMES:

SID_LIST_LISTENER=
    (SID_LIST=

         (SID_DESC=
           (SID_NAME=db1)
           (ORACLE_HOME=/u01/app/oracle/product/9.2.0)
           (GLOBAL_DBNAME=db1.world)
          )
         (SID_DESC=
           (SID_NAME=db2)
           (ORACLE_HOME=/u01/app/oracle/product/8.1.7)
           (GLOBAL_DBNAME=db2.world)
          )
        )

This implies you should have your correctly set your global_dbname, either at database creation time or via the "alter database rename global_name to ..." command.

You can then either copy an identical tnsnames.ora file to each ORACLE_HOME/network/admin directory, or as you mentioned, use TNS_ADMIN setting to explicitly use one no matter what your current $ORACLE_HOME setting.

Chapter 12 of the 9i Net Services Administrator Guide (or the corresponding 10g version) has all the information and examples you should need. The netca utility is a GUI interface for handling all this for you, as an alternative.

http://download-west.oracle.com/docs/cd/B10501_01/network.920/a96580/listener.htm

-Mark Bole Received on Tue Feb 22 2005 - 12:09:22 CST