RHEL 5.0 IP Network setup

Can someone here please help and walk me through what I need to do to setup
my network so that I can start an oracle listener ?

I am connected through a router (netgear) and everytime I start my machine the ip address changes because of DHCP (I think). There are so many parameters that I do not know what to ignore what not to ignore.

I do not understand why I always have etho and etho.bak as ethernet in Devices tab.

I do not understand the purpose of ipv4 or ipv6.

How can I display what is using up port 1521 ?

If there is someone here who has an idea what is the problem please help.

Thanks

on 1521 by default there's an Oracle Net Listener process, but what exactly you are trying to achieve ? Install Oracle ? If yes, that may not be such a simple matter, you should consult your network or system administrator, and better understand on what hardware and why you are installing there. I guess there's a UI involved, either KDE or GNOME, or whatever, but Oracle can be installed silently, as long as you have all the packages installed.

I have oracle installed but I am not able to start the listener.

I am the owner of my test box. Ihave root access. I am reaching out here to get help configuring my setup so that I can start the listener. I have never installed oracle silently and I am not how that can resolve my problem.

How can I confirm that port 1521 is open and being used by a process ?
netstat and lsof cannot display anything regarding that port. I am thinking I am not using those commands right.

what about telnet to that port and the ip of the machine running the process.

As far as I know, you need a static IP address for the Oracle Listener to work. If the Oracle database is on your system and you do not need to access the database from another system, you could use the loopback address 127.0.0.1.

I just wanted to point out that recently i was installing RHEL 5.5 and found that the Ethernet ports were down by default. Can you do an ifconfig in the terminal and ensure you've been allocated an IP address? It should be a 192.168.x.x. I edited the eth0 config file. (Or Whatever port you've plugged in) This late at night i'm not going to do the searching. But i definitely let google solve my problem. If indeed you're dealing with the same issue.

I'm going to make this basic assumption under the fact that the OP doesn't know the difference between ipv4 and 6. Please.. No offense anyone.