Script to Monitor Database Listener

Pre-requisites to Run the script:

Make sure mailx is installed on your OS, also check below environements/file is created prior to execute the scripts.

This script is tested on Linux Server.

This script needs to be deployed in database node/server.

#Base location for the DBA scripts
DBA_SCRIPTS_HOME=$HOME/DBA_MON

#OS User profile where database environment file is set
$HOME/.bash_profile

Create Custom .sysenv file for scripts

Download(.sysenv)

Download .sysenv file and save it under $HOME/DBA_MON
$ chmod 777 .sysenv

$ cat $HOME/DBA_MON/.sysenv

export DBA_SCRIPTS_HOME=$HOME/DBA_MON
export PATH=${PATH}:$DBA_SCRIPTS_HOME
export DBA_EMAIL_LIST=kiran.jadhav@domain.com,jadhav.kiran@domain.com
#Below parameter is used in script, whenever there is planned downtime you can set it to Y so there will be no false alert.
export DOWNTIME_MODE=N

Script to monitor Database Listener, if down then notify to DBA Team.



Download(MonDBListener.sh)

Download MonDBListener.sh and save it under $HOME/DBA_MON/bin/
$ chmod 755 MonDBListener.sh

#!/bin/bash

###################################################################
# Script Name : MonDBListener.sh                                  #
#                                                                 #
# Description:                                                    #
# Script to monitor Database Listener.                            #
# If down then notify the DBA Team.                               #
#                                                                 #
# Usage : sh <script_name> <ORACLE_SID>                           #
# For example : sh MonDBListener.sh ORCL                          #
#                                                                 #
# Created by : Kiran Jadhav - (https://h2hdba.blogspot.com)       #
###################################################################

# Initialize variables

INSTANCE=$1
HOST_NAME=`hostname | cut -d'.' -f1`
PROGRAM=`basename $0 | cut -d'.' -f1`
export DBA_SCRIPTS_HOME=$HOME/DBA_MON
APPS_ID=`echo $INSTANCE | tr '[:lower:]' '[:upper:]'`
LOG_DIR=$DBA_SCRIPTS_HOME/logs/$HOST_NAME
OUT_FILE=$LOG_DIR/`echo $PROGRAM`_$APPS_ID.out
LOG_FILE=$LOG_DIR/`echo $PROGRAM`_$APPS_ID.log
ERR_FILE=$LOG_DIR/`echo $PROGRAM`_$APPS_ID.err
LOG_DATE=`date`


# Source the env
. $HOME/.bash_profile
. $DBA_SCRIPTS_HOME/.sysenv

if [ $? -ne 0 ]; then
   echo "$LOG_DATE" > $LOG_FILE  
   echo "Please pass correct environment : exiting the script  \n" >> $LOG_FILE
   cat $LOG_FILE
   exit
fi

if [ -s $OUT_FILE ]; then
 echo "$LOG_DATE" > $LOG_FILE
 echo "Deleting existing output file $OUT_FILE" >> $LOG_FILE
 rm -f $OUT_FILE
 cat $LOG_FILE
fi

# If there is a planned downtime then create $ORACLE_SID.down file in $DBA_SCRIPTS_HOME to silent the alerts during maintenance window.

if [ -f $DBA_SCRIPTS_HOME/`echo $ORACLE_SID`.down ]; then
 echo "$LOG_DATE" >> $LOG_FILE
        echo "Host: $HOST_NAME | Instance: $ORACLE_SID is under maintenance: exiting the script" >> $LOG_FILE
        cat $LOG_FILE
 exit
fi

if [ $DOWNTIME_MODE = "Y" ]; then
 echo "$LOG_DATE" >> $LOG_FILE
 echo "Host: $HOST_NAME | Instance: $ORACLE_SID is under maintenance: exiting the script" >> $LOG_FILE
 cat $LOG_FILE
 exit
fi

usage()
{
  echo "$LOG_DATE" > $LOG_FILE
        echo "Script to monitor Database Listener availability"  >> $LOG_FILE
        echo "Usage   : sh <script_name> <ORACLE_SID> " >> $LOG_FILE
  echo "For example : sh $PROGRAM.sh $ORACLE_SID" >> $LOG_FILE
        echo
}

if [ $# -lt 1 ] || [ "$INSTANCE" != "$ORACLE_SID" ]; then
    usage
    echo "Error : Insufficient arguments." >> $LOG_FILE
 cat $LOG_FILE
    exit
fi

check_listener()
{
 listener=`ps -ef|grep -i "lsnr $ORACLE_SID"|grep -v grep | wc -l`
 echo $listener
}
 
count_listener=`check_listener`
#echo $count_listener


if [ `check_listener` -eq 0 ]; then
 echo "$APPS_ID Database LISTENER is DOWN. Please check ASAP!!!"| mailx -s "Critical : $APPS_ID Database LISTENER is DOWN on $HOST_NAME" $DBA_EMAIL_LIST 
else
 echo "$LOG_DATE" > $OUT_FILE
 echo "$APPS_ID Database LISTENER is up and running fine" >> $OUT_FILE
fi

Logs and Out files will be generated under $DBA_SCRIPTS_HOME/logs/$HOST_NAME
So make sure to create logs/$HOST_NAME directory under $DBA_SCRIPTS_HOME before executing 
the script.

Once the script is ready, then as per the requirement please schedule it in crontab/OEM.

Execute the Script as below:

Syntax :  sh <script_name> <ORACLE_SID> 

$ cd $HOME/DBA_MON/bin
$ sh MonDBListener.sh ORCL

This script will send the notification if database listener is down or unavailable.