#!/bin/bash
#
# Icinga plugin for checking MySQL replication status
#
# Author: Refactored for Icinga
#

MYSQL_USER="root"
MYSQL_PASS=""
MYSQL_SOCKET="/var/lib/mysql/mysql.sock"

# Performance thresholds
DELAY_OK=600
DELAY_WARNING=43200

MYSQL_STATUS=$(mysql --defaults-extra-file="/root/.my.cnf" -u$MYSQL_USER -S $MYSQL_SOCKET -e "SHOW SLAVE STATUS\G" | grep -E 'Slave_.*_Running|Seconds_Behind_Master' | sed 's/^ *//')

IO_RUNNING=$(echo "$MYSQL_STATUS" | grep "Slave_IO_Running:" | awk '{print $2}')
SQL_RUNNING=$(echo "$MYSQL_STATUS" | grep "Slave_SQL_Running:" | awk '{print $2}')
DELAY=$(echo "$MYSQL_STATUS" | grep "Seconds_Behind_Master:" | awk '{print $2}')

EXIT_CODE=0

if [[ "$IO_RUNNING" != "Yes" ]]; then
  OUTPUT="CRITICAL - Replication IO Stopped"
  EXIT_CODE=2
elif [[ "$SQL_RUNNING" != "Yes" ]]; then
  OUTPUT="CRITICAL - Replication SQL Stopped"
  EXIT_CODE=2
elif [[ "$DELAY" == "NULL" ]]; then
  OUTPUT="CRITICAL - Replication delay is NULL"
  EXIT_CODE=2
elif (( DELAY < DELAY_OK )); then
  OUTPUT="OK - MySQL Replication is running with delay $DELAY seconds"
elif (( DELAY < DELAY_WARNING )); then
  OUTPUT="WARNING - Replication delay $DELAY seconds"
  EXIT_CODE=1
else
  OUTPUT="CRITICAL - Replication delay $DELAY seconds"
  EXIT_CODE=2
fi

# Print output for Icinga
echo "$OUTPUT | delay=$DELAY;$DELAY_OK;$DELAY_WARNING;;"
exit $EXIT_CODE