My TNS listener stopped working

From: Mike Harrison <harrisonm7_at_home.com>
Date: 12 Apr 2002 08:04:25 -0700
Message-ID: <471417c6.0204120704.3f52f4bf@posting.google.com>

The TNS Listener for our Oracle 8.1.6 (NT4 sp6) server seems to have stopped working all of a sudden. Nothing happened on the server that I'm aware, but now all I get is

ORA-12543: TNS:destination host unreachable

when I try to log into the database with SQLPLUS. The listener's log file seems to indicate that the connection was established:

12-APR-2002 10:55:07 *
(CONNECT_DATA=(SERVICE_NAME=oracle8.world)(CID=(PROGRAM=c:\orant\bin\SQLPLUS.EXE)(HOST=HOSTNAMEDELETED)(USER=USERNAME))) * (ADDRESS=(PROTOCOL=tcp)(HOST=xx.xx.xx.xx)(PORT=1249)) * establish * oracle8.world * 0

The entry in the tnsnames.ora:

ORACLE8 =
  (DESCRIPTION =
(ADDRESS_LIST =

      (ADDRESS = (PROTOCOL = TCP)(HOST = servername)(PORT = 1521))     )
(CONNECT_DATA =

      (SERVICE_NAME = oracle8.world)
    )
  )
What would be the cause of this problem? I can log into the database with sqlplus from the server itself, just not from a client. I haven't changed the tnsnames.ora or listener.ora file on the server at all. I can TNSPING the server and it says "OK". I've tried stopping and starting the TNS listener to no avail. Everything was working fine with this database yesterday. Received on Fri Apr 12 2002 - 10:04:25 CDT