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TCP/IP problem

A z/OS newbie wrote in asking for help with TCP/IP addresses. Expert Mark Zelden tries to help and directs him to a place where he can read more about it.

We're running z/OS Version 1.4.10 on a 2066-0A1 z/Series 800. I need to add two new ports to TCP/IP to be used for Cobol CICS Socket programming. The ports are 3010 & 3011. EZACICD has been modified to direct it to our Test CICS region named OKDPSTST. Port=3011. Problem is, when you use NETSTAT from TSO, it lists 3010 & 3011, but does not reflect that the system knows about an associate to the IP Address for the host port and its association to 3010 & 3011. It reflects and not 172.xx.xx.xxx. What do I have to have modified and recycled in order for these associations to be completed? Thanks. New to z/OS Systems.

I'm not sure I understand the question well (part of that may be that I am not a "TCP/IP expert". How does it list those ports? As listening or established? It sounds like it is just listening which means it is just waiting for a connection. So perhaps your application is just not working or trying to use the port when you are using the NETSTAT command.

There are parms within TCP/IP that restrict port usage by range and parms that reserve ports for certain job names. However, it is not required to reserve the port to a particular job (but it is good practice). Those port assignments can be made in the "MVS" stack within the TCP/IP parms or from the Unix stack (/etc/services).

For more information, please see the various TCP/IP manuals on the z/OS Communications Server bookshelf: http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/Shelves/F1A1BK5.

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