This actually can work real nice if set up correctly. The following discussion is relevant to HP and may or=20 may not apply the architecture you are using. On hp, when using service guard for clustering, units of=20 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=20 appears that if you run a listener configured to listen on the IP = address of the=20 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=20 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----- From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx]On Behalf Of JayMiller@xxxxxxxxxxxxxxxx Sent: Monday, March 21, 2005 1:18 PM To: oracle-l@xxxxxxxxxxxxx Subject: Any way to run more than listener on the same port? Hi, 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? Thanks, Jay Miller -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l