1 Listener Control Utility

This chapter describes the commands and associated syntax of the Listener Control utility.

This chapter contains the following topics:

Listener Control Utility Overview

The Listener Control utility enables you to administer listeners.You can use its commands to perform basic management functions on one or more listeners. Additionally, you can view and change parameter settings.

The basic syntax of Listener Control utility commands is as follows:

lsnrctl command listener_name

In the preceding command, listener_name is the name of the listener to be administered. If no name is specified, then the default name, LISTENER, is assumed.

You can also issue Listener Control utility commands at the LSNRCTL> program prompt. To obtain the prompt, enter lsnrctl with no arguments at the operating system command line. When you run lsnrctl, the program is started. You can then enter the necessary commands from the program prompt. The basic syntax of issuing commands from LSNRCTL> program prompt is as follows:

lsnrctl
LSNRCTL> command listener_name

Note:

You can combine commands in a standard text file, and then run them as a sequence of commands. To execute in batch mode, use the format:

lsnrctl @file_name

You can use either REM or # to identify comments in the batch script; all other lines are considered commands. Any commands that would typically require confirmation do not require confirmation during batch execution.

For most commands, the Listener Control utility establishes an Oracle Net connection with the listener that is used to transmit the command. To initiate an Oracle Net connection to the listener, the Listener Control utility must obtain the protocol addresses for the named listener or a listener named LISTENER. This is done by resolving the listener name with one of the following mechanisms:

  • listener.ora file in the directory specified by the TNS_ADMIN environment variable

  • listener.ora file in the ORACLE_HOME/network/admin directory.

  • Naming method, for example, a tnsnames.ora file

If none of the preceding mechanisms resolve the listener name, then the Listener Control utility uses the default listener name LISTENER, resolves the host name IP address and uses port 1521.

The Listener Control utility supports several types of commands:

  • Operational commands, such as START, and STOP.

  • Modifier commands, such as SET TRC_LEVEL.

  • Informational commands, such as STATUS and SHOW LOG_FILE.

SET and SHOW Commands of the Listener Control utility

You can use the SET command to alter parameter values for a specified listener. You set the name of the listener you want to administer with the SET CURRENT_LISTENER command. Parameter values remain in effect until the listener is shut down. If you want these settings to persist, then use the SAVE_CONFIG command to save changes to the listener.ora.

You can use the SHOW command to display the current value of a configuration setting.

Distributed Operations

The Listener Control utility can perform operations on a local or a remote listener.

To set up a computer to remotely administer a listener, do the following:

  1. Ensure that the Listener Control utility (lsnrctl) executable is installed in the ORACLE_HOME/bin directory.

  2. Ensure that the name of the listener you want to administer can be resolved through a listener.ora file or a naming method, as described in "Listener Control Utility Overview".

All commands except START can be issued when a listener is administered remotely. The Listener Control utility can only start the listener on the same computer from where the utility is running.

When issuing commands, specify the listener name as an argument. For example:

LSNRCTL> SERVICES lsnr

If the name is omitted, then listener name set with the SET CURRENT_LISTENER command is used, or the default name, LISTENER is assumed.

Oracle Net Listener Security

Local listener administration is secure through local operating system authentication, which restricts listener administration to the user who started the listener or to the super user. By default, remote listener administration is disabled.

Oracle recommends that you perform listener administration in the default mode, and access the system remotely using a remote login. When you administer the listener remotely, use Oracle Enterprise Manager or Secure Shell (SSH) to access the remote host.

Listener Control Utility Commands

This section describes the following Listener Control utility commands:

EXIT

Purpose

To exit from the Listener Control utility, and return to the operating system prompt.

Prerequisites

None

Syntax

From the Listener Control utility:

LSNRCTL> EXIT

Arguments

None

Usage Notes

This command is identical to the QUIT command.

Example

LSNRCTL> EXIT

HELP

Purpose

To provide a list of all the Listener Control utility commands or provide syntax help for a particular Listener Control utility command.

Prerequisites

None

Syntax

From the operating system:

lsnrctl HELP command

From the Listener Control utility:

LSNRCTL> HELP command

Arguments

command: The Listener Control utility command. Commands are shown in the following example output.

When you enter a command as an argument to HELP, the Listener Control utility displays information about how to use the command. When you enter HELP without an argument, the Listener Control utility displays a list of all the commands.

Example

LSNRCTL> HELP
The following operations are available 
An asterisk (*) denotes a modifier or extended command: 
exit 
quit
reload 
services 
set* 
show*
spawn 
start                          
status 
stop 
trace          
version 

QUIT

Purpose

To exit the Listener Control utility and return to the operating system prompt.

Prerequisites

None

Syntax

From the Listener Control utility

LSNRCTL> QUIT

Arguments

None

Usage Notes

This command is identical to the EXIT command.

Example

LSNRCTL> QUIT

RELOAD

Purpose

To reread the listener.ora file. This command enables you to add or change statically configured services without actually stopping the listener.

In addition, the database services, instances, service handlers, and listening endpoints that were dynamically registered with the listener are unregistered and subsequently registered again.

Prerequisites

None

Syntax

From the operating system:

lsnrctl RELOAD listener_name

From the Listener Control utility:

LSNRCTL> RELOAD listener_name

Arguments

listener_name: The listener name, if the default name of LISTENER is not used.

Example

LSNRCTL> RELOAD
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=sales-server)(PORT=1521)))
The command completed successfully

SAVE_CONFIG

Purpose

To save the current configuration state of the listener, including trace level, trace file, trace directory, and logging to the listener.ora file. Any changes are stored in listener.ora, preserving formatting, comments, and case as much as possible. Before modification of the listener.ora file, a backup of the file, called listener.bak, is created.

Syntax

From the operating system:

lsnrctl SAVE_CONFIG listener_name

From the Listener Control utility:

LSNRCTL> SAVE_CONFIG listener_name

Arguments

listener_name: The listener name, if the default name of LISTENER is not used.

Usage Notes

This command enables you to save all run-time configuration changes to the listener.ora file.

Example

LSNRCTL> SAVE_CONFIG listener
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=sales-server)(PORT=1521)))
Saved LISTENER configuration parameters.
Listener Parameter File   /oracle/network/admin/listener.ora
Old Parameter File   /oracle/network/admin/listener.bak
The command completed successfully

SERVICES

Purpose

To obtain detailed information about the database services, instances, and service handlers (dispatchers and dedicated servers) to which the listener forwards client connection requests.

Prerequisites

None

Syntax

From the operating system:

lsnrctl SERVICES listener_name

From the Listener Control utility:

LSNRCTL> SERVICES listener_name

Arguments

listener_name: The listener name, if the default name of LISTENER is not used.

Usage Notes

The SET DISPLAYMODE command changes the format and the detail level of the output.

See Also:

Oracle Database Net Services Administrator's Guide for a complete description of SERVICES output

Example

This example shows SERVICES output in the default display mode. The output shows the following:

  • An instance named sales belonging to two services, sales1.us.example.com and sales2.us.example.com, with a total of three service handlers.

  • Service sales1.us.example.com is handled by one dispatcher only.

  • Service sales2.us.example.com is handled by one dispatcher and one dedicated server, as specified by in the following output.

LSNRCTL> SERVICES
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=net)))
Services Summary...
Service "sales1.us.example.com" has 1 instance(s).
  Instance "sales", status READY, has 1 handler(s) for this service...
    Handler(s):
      "D000" established:0 refused:0 current:0 max:10000 state:ready
         DISPATCHER <machine: sales-server, pid: 5696>
         (ADDRESS=(PROTOCOL=tcp)(HOST=sales-server)(PORT=53411))
Service "sales2.us.example.com" has 1 instance(s).
  Instance "sales", status READY, has 2 handler(s) for this service...
    Handler(s):
      "DEDICATED" established:0 refused:0 state:ready
         LOCAL SERVER
      "D001" established:0 refused:0 current:0 max:10000 state:ready
         DISPATCHER <machine: sales-server, pid: 5698>
         (ADDRESS=(PROTOCOL=tcp)(HOST=sales-server)(PORT=52618))
The command completed successfully

SET

Purpose

To alter the parameter values for the listener. Parameter value changes remain in effect until the listener is shut down. To make the changes permanent, use the SAVE_CONFIG command to save changes to the listener.ora file.

Prerequisites

None

Syntax

From the operating system:

lsnrctl SET parameter

From the Listener Control utility:

LSNRCTL> SET parameter

Arguments

parameter: A SET parameter to modify its configuration setting. Parameters are shown in the example output.

When you enter SET without an argument, the Listener Control utility displays a list of all the parameters.

Usage Notes

If you are using the SET commands to alter the configuration of a listener other than the default LISTENER listener, then use the SET CURRENT_LISTENER command to set the name of the listener you want to administer.

Example

LSNRCTL> SET
The following operations are available with set.
An asterick (*) denotes a modifier or extended command.
current_listener 
displaymode
inbound_connect_timeout
log_file
log_directory
log_status
rawmode
save_config_on_stop 
trc_file
trc_directory
trc_level 

SET CURRENT_LISTENER

Purpose

To set the name of the listener to administer. Subsequent commands that would normally require listener_name can be issued without it.

Syntax

From the Listener Control utility

LSNRCTL> SET CURRENT_LISTENER listener_name

Arguments

listener_name: The listener name, if the default name of LISTENER is not used.

Usage Notes

When SET CURRENT_LISTENER is set, the Listener Control utility commands act on the listener you set. You do not have to specify the name of the listener.

Example

LSNRCTL> SET CURRENT_LISTENER lsnr
Current Listener is lsnr

SET DISPLAYMODE

Purpose

To change the format and level of detail for the SERVICES and STATUS commands.

Syntax

From the Listener Control utility:

LSNRCTL> SET DISPLAYMODE {compat | normal | verbose | raw}

Arguments

Specify one of the following modes:

compat: Output that is compatible with older versions of the listener.

normal: Output that is formatted and descriptive. Oracle recommends this mode.

verbose: All data received from the listener in a formatted and descriptive output.

raw: All data received from the listener without any formatting. This argument should be used only if recommended by Oracle Support Services.

Example

LSNRCTL> SET DISPLAYMODE normal
Service display mode is NORMAL

SET INBOUND_CONNECT_TIMEOUT

Purpose

To specify the time, in seconds, for the client to complete its connect request to the listener after establishing the network connection.

If the listener does not receive the client request in the time specified, then it terminates the connection. In addition, the listener logs the IP address of the client and an ORA-12525:TNS: listener has not received client's request in time allowed error message to the listener.log file.

See Also:

Oracle Database Net Services Administrator's Guide for additional information about specifying the time out for client connections

Syntax

From the Listener Control utility:

LSNRCTL> SET INBOUND_CONNECT_TIMEOUT time

Arguments

time: The time, in seconds. Default setting is 60 seconds.

Example

LSNRCTL> SET INBOUND_CONNECT_TIMEOUT 2
Connecting to (ADDRESS=(PROTOCOL=TCP)(HOST=sales-server)(PORT=1521))
LISTENER parameter "inbound_connect_timeout" set to 2
The command completed successfully.

SET LOG_DIRECTORY

Note:

This command works only if Automatic Diagnostic Repository (ADR) is not enabled. The default is for ADR to be enabled, and the log directory is ORACLE_HOME/log/diag/product_type.

Purpose

To set destination directory where the listener log file is written. By default, the log file is written to the ORACLE_HOME/network/log directory.

Prerequisites

None

Syntax

From the operating system:

lsnrctl SET LOG_DIRECTORY directory

From the Listener Control utility:

LSNRCTL> SET LOG_DIRECTORY directory

Arguments

directory: The directory path of the listener log file.

Example

LSNRCTL> SET LOG_DIRECTORY /usr/oracle/admin 
Connecting to (ADDRESS=(PROTOCOL=TCP)(HOST=sales-server)(PORT=1521))
LISTENER parameter "log_directory" set to /usr/oracle/admin
The command completed successfully

SET LOG_FILE

Note:

This command works only if Automatic Diagnostic Repository (ADR) is not enabled. The default is for ADR to be enabled, and the log directory is ORACLE_HOME/log/diag/product_type.

Purpose

To set the name for the listener log file. By default, the log file name is listener.log.

Prerequisites

None

Syntax

From the operating system:

lsnrctl SET LOG_FILE file_name

From the Listener Control utility:

LSNRCTL> SET LOG_FILE file_name

Arguments

file_name: The file name of the listener log.

Example

LSNRCTL> SET LOG_FILE list.log
Connecting to (ADDRESS=(PROTOCOL=TCP)(HOST=sales-server)(PORT=1521))
LISTENER parameter "log_file" set to list.log
The command completed successfully

SET LOG_STATUS

Purpose

To turn listener logging on or off.

Prerequisites

None

Syntax

From the operating system:

lsnrctl SET LOG_STATUS {on | off}

From the Listener Control utility:

LSNRCTL> SET LOG_STATUS {on | off}

Arguments

on: To turn logging on.

off: To turn logging off.

Example

LSNRCTL> SET LOG_STATUS on
Connecting to (ADDRESS=(PROTOCOL=TCP)(HOST=sales-server)(PORT=1521))
LISTENER parameter "log_status" set to ON
The command completed successfully

SET SAVE_CONFIG_ON_STOP

Purpose

To specify whether changes made to the parameter values for the listener by the SET commands are to be saved to the listener.ora file at the time the listener is stopped with the STOP command.

When changes are saved, the Listener Control utility tries to preserve formatting, comments, and letter case. Before modification of the listener.ora file, a back up of the file, called listener.bak, is created.

To have all parameters saved immediately, use the SAVE_CONFIG command.

Syntax

From the operating system:

lsnrctl SET SAVE_CONFIG_ON_STOP  {on | off}

From the Listener Control utility:

LSNRCTL> SET SAVE_CONFIG_ON_STOP  {on | off}

Arguments

on: To save configuration to listener.ora.

off: To not save configuration to listener.ora.

Example

LSNRCTL> SET SAVE_CONFIG_ON_STOP on
LISTENER parameter "save_config_on_stop" set to ON
The command completed successfully

SET TRC_DIRECTORY

Note:

This command works only if Automatic Diagnostic Repository (ADR) is not enabled. The default is for ADR to be enabled, and the log directory is ORACLE_HOME/log/diag/product_type.

Purpose

To set the destination directory where the listener trace files are written. By default, the trace file are written to the ORACLE_HOME/network/trace directory.

Prerequisites

None

Syntax

From the operating system:

lsnrctl SET TRC_DIRECTORY directory

From the Listener Control utility:

LSNRCTL> SET TRC_DIRECTORY directory

Arguments

directory: The directory path of the listener trace files.

Example

LSNRCTL> SET TRC_DIRECTORY /usr/oracle/admin
Connecting to (ADDRESS=(PROTOCOL=TCP)(HOST=sales-server)(PORT=1521))
LISTENER parameter "trc_directory" set to /usr/oracle/admin
The command completed successfully

SET TRC_FILE

Note:

This command works only if Automatic Diagnostic Repository (ADR) is not enabled. The default is for ADR to be enabled, and the log directory is ORACLE_HOME/log/diag/product_type.

Purpose

To set the name of the listener trace file. By default, the trace file name is listener.trc.

Prerequisites

None

Syntax

From the operating system:

lsnrctl SET TRC_FILE file_name

From the Listener Control utility:

LSNRCTL> SET TRC_FILE file_name

Arguments

file_name: The file name of the listener trace.

Example

LSNRCTL> SET TRC_FILE list.trc
Connecting to (ADDRESS=(PROTOCOL=TCP)(HOST=sales-server)(PORT=1521))
LISTENER parameter "trc_file" set to list.trc
The command completed successfully

SET TRC_LEVEL

Purpose

To set a specific level of tracing for the listener.

Prerequisites

None

Syntax

From the operating system:

lsnrctl SET TRC_LEVEL level

From the Listener Control utility:

LSNRCTL> SET TRC_LEVEL level

Arguments

level: One of the following trace levels:

  • off for no trace output

  • user for user trace information

  • admin for administration trace information

  • support for Oracle Support Services trace information

Usage Notes

This command has the same functionality as the TRACE command.

Example

LSNRCTL> SET TRC_LEVEL admin
Connecting to (ADDRESS=(PROTOCOL=TCP)(HOST=sales-server)(PORT=1521))
LISTENER parameter "trc_level" set to admin
The command completed successfully

SHOW

Purpose

To view the current parameter values for the listener.

All of the SET parameters have equivalent SHOW parameters.

Prerequisites

None

Syntax

From the operating system:

lsnrctl SHOW parameter

From the Listener Control utility:

LSNRCTL> SHOW parameter

Arguments

parameter: A SHOW parameter to view its configuration settings. Parameters are shown in the example output.

When you enter SHOW without an argument, the Listener Control utility displays a list of all the parameters.

Example

LSNRCTL> SHOW
The following properties are available with SHOW:
An asterisk (*) denotes a modifier or extended command:
current_listener 
displaymode
inbound_connect_timeout
log_file
log_directory
log_status
rawmode
save_config_on_stop 
trc_file
trc_directory
trc_level 

SPAWN

Purpose

To start a program stored on the computer on which the listener is running, and which is listed with an alias in the listener.ora file.

Prerequisites

None

Syntax

From the operating system:

lsnrctl SPAWN listener_name alias (arguments='arg1,arg2,...')

From the Listener Control utility

LSNRCTL> SPAWN listener_name alias (arguments='arg1,arg2,...')

Arguments

listener_name: The listener name, if the default name of LISTENER is not used.

alias: The alias of the program to be spawned off is specified by a listener.ora file entry, similar to the following:

alias = (PROGRAM=(NAME=)(ARGS=)(ENVS=))

For example:

nstest = (PROGRAM=(NAME=nstest)(ARGS=test1)(ENVS='ORACLE_HOME=/usr/oracle'))

Example

This program can then be spawned off using the following command:

lsnrctl SPAWN listener_name nstest

START

Purpose

To start the named listener.

Prerequisites

Listener must not be running.

Syntax

From the operating system:

lsnrctl START listener_name

From the Listener Control utility:

LSNRCTL> START listener_name

Arguments

listener_name: The listener name, if the default name of LISTENER is not used.

Usage Notes

To start a listener configured in the listener.ora file with a name other than LISTENER, include that name.

For example, if the listener name is tcp_lsnr, enter:

lsnrctl START tcp_lsnr 

From the Listener Control utility:

LSNRCTL> START tcp_lsnr

Example

LSNRCTL> START

Starting /private/sales_group/sales/bin/tnslsnr: please wait...

TNSLSNR for Linux: Version 11.2.0.0.0 
System parameter file is /oracle/network/admin/listener.ora
Log messages written to /oracle/network/log/listener.log
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=sales-server)(PORT=1521)))

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=sales-server)(PORT=1521)))
STATUS of the LISTENER
------------------------
Alias                     LISTENER
Version                   TNSLSNR for Linux: Version 11.2.0.0.0 
Start Date                15-NOV-2008 18:02:25
Uptime                    0 days 0 hr. 0 min. 0 sec
Trace Level               off
Security                  OFF
SNMP                      OFF
Listener Parameter File   /oracle/network/admin/listener.ora
Listener Log File         /oracle/network/log/listener.log
Listening Endpoints Summary...
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=sales-server)(PORT=1521)))
The listener supports no services
The command completed successfully

STATUS

Purpose

To display basic status information about a listener, including a summary of listener configuration settings, listening protocol addresses, and a summary of services registered with the listener.

Note:

You can also obtain the status of the listener through the Oracle Enterprise Manager Console. See the Oracle Database 2 Day DBA for additional information.

Prerequisites

None

Syntax

From the operating system:

lsnrctl STATUS listener_name

From the Listener Control utility:

LSNRCTL> STATUS listener_name 

Arguments

listener_name: The listener name, if the default name of LISTENER is not used.

Usage Notes

The SET DISPLAYMODE command changes the format and level of the detail of the output.

See Also:

Oracle Database Net Services Administrator's Guide for a complete description of STATUS output

Example

The following example shows STATUS output in the default display mode. The output contains:

  • Listener configuration settings

  • Listening endpoints summary

  • Services summary, which is an abbreviated version of the SERVICES command output

LSNRCTL> STATUS
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=net)))
STATUS of the LISTENER
------------------------
Alias                     LISTENER
Version                   TNSLSNR for Linux: Version 11.2.0.0.0 -
Beta
Start Date                15-JAN-2008 12:02:00
Uptime                    0 days 0 hr. 5 min. 29 sec
Trace Level               support
Security                  OFF
SNMP                      OFF
Listener Parameter File   /oracle/network/admin/listener.ora
Listener Log File         /oracle/network/log/listener.log
Listener Trace File       /oracle/network/trace/listener.trc

Listening Endpoints Summary...
  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=net)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=sales-server)(PORT=1521)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcps)(HOST=sales-server)(PORT=2484)))
 
Services Summary...
Service "sales1.us.example.com" has 1 instance(s).
  Instance "sales", status READY, has 1 handler(s) for this service...
Service "sales2.us.example.com" has 1 instance(s).
  Instance "sales", status READY, has 2 handler(s) for this service...
The command completed successfully

STOP

Purpose

To stop the named listener.

Prerequisites

The listener must be running.

Syntax

From the operating system:

lsnrctl STOP listener_name
 

From the Listener Control utility:

LSNRCTL> STOP listener_name 

Arguments

listener_name: The listener name, if the default name of LISTENER is not used.

Example

LSNRCTL> STOP
Connecting to (ADDRESS=(PROTOCOL=TCP)(HOST=sales-server)(PORT=1521))
The command completed successfully

TRACE

Purpose

To turn on tracing for the listener.

Syntax

From the operating system:

lsnrctl trace level listener_name

From the Listener Control utility:

LSNRCTL> trace level listener_name

Arguments

level: One of the following trace levels:

  • off for no trace output

  • user for user trace information

  • admin for administration trace information

  • support for Oracle Support Services trace information

listener_name: Specify the listener name, if the default name of LISTENER is not used.

Usage Notes

This command has the same functionality as SET TRC_LEVEL command.

Example

LSNRCTL> TRACE ADMIN lsnr
Connecting to (ADDRESS=(PROTOCOL=TCP)(HOST=sales-server)(PORT=1521))
Opened trace file: /oracle/network/trace/listener.trc
The command completed successfully

VERSION

Purpose

To display the current version of Listener Control utility.

Prerequisites

None

Syntax

From the operating system:

lsnrctl VERSION listener_name

From the Listener Control utility:

LSNRCTL> VERSION listener_name

Arguments

listener_name: The listener name, if the default name of LISTENER is not used.

Example

LSNRCTL> VERSION listener1
Connecting to ADDRESS=(PROTOCOL=TCP)(HOST=sales-server)(PORT=1521))
TNSLSNR for Linux: Version 11.2.0.0.0
        TNS for Linux: Version 11.2.0.0.0 
        Oracle Bequeath NT Protocol Adapter for Linux: Version 11.2.0.0.0
        Unix Domain Socket IPC NT Protocol Adaptor for Linux: Version 11.2.0.0.0 
        TCP/IP NT Protocol Adapter for Linux: Version 11.2.0.0.0
The command completed successfully