strange tns listener problem..

From: DJH <NOSPAM_at_NOSPAM.COM>
Date: Tue, 09 Oct 2007 15:49:10 -0400
Message-ID: <13gnmpodkjjj338@news.supernews.com>

I am having a strange situation where the service seems to disappear from the tns listener "registry". Is there a way to force oracle to re-register with the listener?

In the following examples you will see "cu" appear initially then disappear in the next "stat."

also if you try to connect this is what you get:

xxwww:15:44:/root> sqlplus xxx/xxx_at_cu

ERROR:
ORA-12514: TNS:listener does not currently know of service requested in connect
descriptor

Enter user-name:
ERROR:
ORA-12154: TNS:could not resolve the connect identifier specified

SP2-0157: unable to CONNECT to ORACLE after 3 attempts, exiting SQL*Plus

Thanks for any help!!

[root_at_db1]~# lsnrctl stat

LSNRCTL for Linux: Version 10.2.0.2.0 - Production on 09-OCT-2007 12:46:21

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1))) STATUS of the LISTENER

Alias                     LISTENER
Version                   TNSLSNR for Linux: Version 10.2.0.2.0 - Production
Start Date                09-OCT-2007 12:44:49
Uptime                    0 days 0 hr. 1 min. 31 sec
Trace Level               off
Security                  ON: Local OS Authentication
SNMP                      OFF

Listener Parameter File
/u01/app/oracle/product/primary/network/admin/listener.ora
Listener Log File
/u01/app/oracle/product/primary/network/log/listener.log
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1))) (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=db1.xxxx.com)(PORT=1521))) Services Summary...
Service "PLSExtProc" has 1 instance(s).
Instance "PLSExtProc", status UNKNOWN, has 1 handler(s) for this service...
Service "cu" has 1 instance(s).

  Instance "cu", status READY, has 1 handler(s) for this service...
Service "cuXDB" has 1 instance(s).
  Instance "cu", status READY, has 1 handler(s) for this service...

Service "cu_XPT" has 1 instance(s).
Instance "cu", status READY, has 1 handler(s) for this service... The command completed successfully

####################################Then LATER cu disappears .....
####################################

[root_at_db1]~# lsnrctl stat

LSNRCTL for Linux: Version 10.2.0.2.0 - Production on 09-OCT-2007 15:02:48

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1))) STATUS of the LISTENER

Alias                     LISTENER
Version                   TNSLSNR for Linux: Version 10.2.0.2.0 - Production
Start Date                09-OCT-2007 12:44:49
Uptime                    0 days 2 hr. 17 min. 59 sec
Trace Level               off
Security                  ON: Local OS Authentication
SNMP                      OFF