2 Replies Latest reply on Aug 11, 2011 11:19 AM by Billy~Verreynne

    TNS-12542: TNS:address already in use

    650575
      I am getting error during listener startup

      lsnrctl start

      Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1)))
      Error listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=localhost.localdomain)(PORT=1521)))
      TNS-12542: TNS:address already in use
      TNS-12560: TNS:protocol adapter error
      TNS-00512: Address already in use
      Linux Error: 98: Address already in use


      thanks in advance
        • 1. Re: TNS-12542: TNS:address already in use
          Helios-GunesEROL
          Hi;

          What is db version?

          Please see:
          Listener Fails to Start on Linux, Errors with TNS-12542, Linux Error: 98: Address already in use [ID 301014.1

          Regard
          Helios                                                                                                                                                                                                                                                                                                                                                   
          • 2. Re: TNS-12542: TNS:address already in use
            Billy~Verreynne
            user647572 wrote:

            Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1)))
            Error listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=localhost.localdomain)(PORT=1521)))
            TNS-12542: TNS:address already in use
            This means that a process (possible even the same listener) is already listening on port 1521 on IP address 127.0.0.1 (aka hostname <i>localhost.localdomain</i>).

            Note that the following address entry (using the hostname of the platform):
            <i>( ADDRESS=(PROTOCOL=TCP)(HOST=myserver.mydomain.com)(PORT=1521) )</i>

            ..instructs the listener to listen on all IP addresses of that platform. Including any new IP addresses that may be dynamically created subsequently.

            Thus if you have a listener configured for the hostname of that platform, then that includes listening on the localhost address of 127.0.0.1. The above error will result if you then attempt to specify localhost again as an explicit IP address to listen on.

            This is not listener specific btw - it is how the basic network socket interface works.