Listener log check

Job details

Name:	Listener log check
Platform:	Oracle
Category:	Availability
Description:	This checks and reads errors from the database listener log. Using Oracle native code to read.
Long description:	This checks and reads errors from the database listener log. Using Oracle native code to read.
Version:	1.8
Default schedule:	7,27,47 * * *
Requires engine install:	Yes
Compatibility tag:	.[type=‘instance’ & databasetype=‘oracle’]/.[hasengine=‘YES’ & (version like ‘10%’) & _priv_read_dba_directories = ‘1′ & can_get_grant_create_any_directory=‘1′]

Name	Default value	Description
listener log name	listener.log	The name of the Listener log file.
listener log path	null	The path name of the Listener log file which is used to create directory object.
listener log directory name	DBW_LISTENER_DIR	The name of the directory object created with the DDL – “create directory”.
listener log error text	TNS-	Defines which strings (errors) the Check must look for. Values for this parameter must be
listener log line HWM	1	Each time the Check read the listener log, it registers how many rows have been checked.
listener log max lines	200000	If the listener log has more lines than the value of this parameter, then the Check terminates
listener log max elapsed time	60	Define the maximum elaps time the Check can execute (values are in seconds). If the execution ‘
listener log error text allowed	TNS-12500	Specifies the error strings which are excluded.

Purpose: The purpose of this job is to monitor and check errors in the database listener log specifically for Oracle instances.
Why: This job is crucial as it ensures that any errors that might affect database connectivity or performance are quickly identified and addressed. Monitoring the listener log helps in proactive maintenance and avoiding potential downtime or performance issues.
Manual checking: You can manually check the database listener log by accessing the log file directly on the server or through database queries if the log is stored in a database accessible format.

Name: “Listener log check”
Description: This monitors and reads errors from the database listener log using Oracle native code.
Category: “Availability”
Version: 1.8
Company: dbwatch.com
Default Schedule: Executes at 07, 27, and 47 minutes past every hour.

The job has dependencies on its own previous runs and some procedures belonging to the alert_log check. It ensures those procedures and checks are in place before running.
Before implementation, the job ensures that the necessary directory privileges are granted for accessing or creating necessary directories.

grant CREATE ANY DIRECTORY to ";;inst-user;;"

The implemented procedure reads from the listener log, checks for specified error texts, and handles large logs efficiently by truncating or skipping already read lines.
Parameters like listener log path, name, error texts, and thresholds for line numbers and execution time are customizable.
Error handling is robust, capturing any exceptions and recording them in a defined error table.

Generates a report based on the listener log check, displaying errors and statuses that help in proactive management of the database environment.

Log Text
Error on listener at 10:10 PM – TNS-00515: Connection Closed

The monitoring job for dbWatch Control Center focused on Oracle listener logs is vital for maintaining database availability and performance by detecting and addressing potential connectivity issues or errors in real-time.