DFHSO0109 `date` `time` `applid` The TCPIPSERVICE `tcpipservice` could not be opened because the port `portnumber` is already in use on the IP address `ipaddress` .


    Explanation
      This message is issued when the open of a TCPIPSERVICE cannot be completed. The port number specified is already in use in combination with the IP address. By default, TCP/IP allows only one server to be listening on a port at any one time.

      Specifically, this message is issued when the TCP/IP bind call fails with a return code of EADDRINUSE.

    

    System action
      The TCPIPSERVICE does not open, but remains closed. An exception trace entry is written detailing the return values from the TCP/IP bind call. An application using the EXEC API to set the TCPIPSERVICE open receives an RESP(INVREQ) RESP2(9).

    

    User response
      Check that there are no other TCPIPSERVICES open using the same port number and IP address as the failing one. If there is another TCPIPSERVICE open using the port, it must be closed before the new one can be opened.

      If no TCPIPSERVICESs are using the requested port, there might be another application acting as a TCP/IP server already listening on the port. Use the TSO command NETSTAT to display TCP/IP servers on the system. Choose an unused port for the TCPIPSERVICE.

      If your system has more than one TCP/IP stack you can specify another stack's IP address on the TCPIPSERVICE definition. This will allow you to install multiple TCPIPSERVICEs each using the same port number. You can also configure support in TCP/IP for virtual IP addresses on a single system. This will also allow more than one TCPIPSERVICE to share the same port.

      Finally, TCP/IP can be configured with port sharing. This allows multiple servers (TCPIPSERVICES) to use the same port with TCP/IP using load balancing to direct incoming connections to the set of servers on the port. If port sharing is enabled, multiple TCPIPSERVICEs can each be opened on the same IP address with the same port, if port sharing is supported by the protocol specified in the TCPIPSERVICE resource definition.

    

    Module
DFHSOCK

    XMEOUT parameters/Message inserts
      
      
        
          date
        

        
          time
        

        
          applid
        

        
          tcpipservice
        

        
          portnumber
        

        
          ipaddress
        

      

    

    Destination
      
      CSOO

DFHSO0109 date time applid The TCPIPSERVICE tcpipservice could not be opened because the port portnumber is already in use on the IP address ipaddress .

Explanation

System action

User response

Module

XMEOUT parameters/Message inserts

Destination

DFHSO0109 `date` `time` `applid` The TCPIPSERVICE `tcpipservice` could not be opened because the port `portnumber` is already in use on the IP address `ipaddress` .