Oracle FAQ Your Portal to the Oracle Knowledge Grid

Home -> Community -> Mailing Lists -> Oracle-L -> RE: Any way to run more than listener on the same port?

RE: Any way to run more than listener on the same port?

From: <>
Date: Mon, 21 Mar 2005 14:33:17 -0500
Message-ID: <5B257A26B4845C469B87871B6CEFE507227F51@usnjc04wmx003>

That was foolish of me.

I'm on Solaris 2.9, Oracle 9.2

Could this be made to work in that environment?


-----Original Message-----

From: Adams, Matthew (GE Consumer & Industrial) [mailto:MATT.ADAMS_at_GE.COM] Sent: Monday, March 21, 2005 2:11 PM
To: Miller, Jay;
Subject: RE: Any way to run more than listener on the same port?

This actually can work real nice if set up correctly.

The following discussion is relevant to HP and may or may not apply the architecture you are using.

On hp, when using service guard for clustering, units of work called packages are allowed to failover between servers.

Each package has a distinct name and IP address. When you are running many packages on a server (each with their own set of databases), you can either have a single listener
that listens all the time for DBs that on that server (dynamicall registering
and de-registering as they enter or leave a particular cluster) or you can set up a listener for each package, which listens on the IP address of the package, not the IP address of the server. All of these listeners can listen on port 1521 for their own IP address with interfering with each other

There is one VERY important caveat to this. If you are running idividual listeners
on the IP address of the packages, you CANNOT run an additional listener that listens
on the server IP address. I'm not sure how it works under the covers, but it
appears that if you run a listener configured to listen on the IP address of the
server, it does a 'lanscan' or something equivalent, finds out all the IP address
being served by the machine (even the package IP address) and will start listener to
port 1521 on EVERY ip address served by the machine. This interferes with the package
specific listeners.

This behavior was observed on 8.1.7 and 9.2.0

Therefore, you limit the listeners to ONLY listening on package address and not on
the server address. This means, essentially, that all databases have to be in
a package and have their own listener (at least if they are going to be on a machine in an HP service guard cluster)

-----Original Message-----

[]On Behalf Of
Sent: Monday, March 21, 2005 1:18 PM
Subject: Any way to run more than listener on the same port?


For portability reasons our Unix SAs would like us to run one listener / instance on the same port of each server.

While I have no problem setting up one listener for two instances or two listeners on different ports I had been under the impression (born out by preliminary experimentation) that you couldn't have more than one listener on the same port.

The Unix SAs say that since they've set up separate Virtual IP Addresses for each instance we should be able to get it to work.

Anyone have any experience with this? Is it possible?

Jay Miller
-- Received on Mon Mar 21 2005 - 14:37:58 CST

Original text of this message