Script to Monitor Database Status or Availability

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 check database status or availability, if down then notify to DBA Team.



Download(DBStatusCheck.sh)

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

#!/bin/bash

######################################################################################
# Script Name : DBStatusCheck.sh                                                     #
#                                                                                    #
# Description:                                                                       #
# Script to check database status or availability, if down then notify the DBA Team. #              #                                                                                    #
#                                                                                    #
# Usage : sh <script_name> <ORACLE_SID>                                              #
# For example : sh DBStatusCheck.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 plan 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 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_db()
{
 sqlplus -s '/as sysdba' <<!
    
 set heading off
 set feedback off
 select count(1) from 
 (
 select name from v\$database
 );
 
    exit;
!
}

count_db=`check_db`
#echo $count_db

check_pmon()
{
 process=`ps -ef|grep ora_pmon_$ORACLE_SID | grep -v grep | wc -l`
 echo $process
}
 
count_pmon=`check_pmon`
#echo $count_pmon

echo "$LOG_DATE" > $ERR_FILE
check_db >> $ERR_FILE
ERR_COUNT=`grep -c "ORA-" $ERR_FILE`

if [ $ERR_COUNT -gt 0 -o `check_pmon` -eq 0 ]; then
    echo "Database $APPS_ID is DOWN!! Please check ASAP"| mailx -s "Critical : Database $APPS_ID is DOWN on $HOST_NAME" $DBA_EMAIL_LIST
else 
    echo "$LOG_DATE" > $OUT_FILE
 echo "Database $APPS_ID 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 DBStatusCheck.sh ORCL

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