lsnrctl services <lsnrname>

LSNRCTL for Linux: Version 10.2.0.1.0 - Production on 28-AUG-2010 09:35:19

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Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=192.9.200.11)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=to_stdby)))
TNS-01189: The listener could not authenticate the user

01189, 00000, "The listener could not authenticate the user"
// *Cause: The user attempted to issue a privileged administrative command, but
// could not be successfully authenticated by the listener using the local OS 
// authentication mechanism. This may occur due to one of the following 
// reasons:
// 1. The user is running a version of LSNRCTL that is lower than the version
//    of the listener.
// 2. The user is attempting to administer the listener from a remote node.
// 3. The listener could not obtain the system resources needed to perform the 
//    authentication.
// 4. The local network connection between the listener and LSNRCTL was 
//    terminated unexpectedly during authentication message exchange, such as 
//    if LSNRCTL program was suddenly aborted.
// 5. The communication between the listener and LSNRCTL is being intercepted
//    by a malicious user.
// 6. The software that the user is running is not following the authentication
//    protocol, indicating a malicious user.
// *Action: Make sure that administrative commands are issued using the LSNRCTL
// tool that is of a version equal or greater than the version of the listener,
// and that the tool and the listener are running on the same node. You can 
// issue the VERSION command to find out the version of the listener. 
// If a malicious user is suspected, use the information provided in 
// the listener log file to determine the source and nature of the requests. 
// Enable listener tracing for more information. If the error persists, 
// contact Oracle Support Services.