Database monitoring

Hi,

I am monitoring database service like pmon,smon, ckpt…by using below script (check_db_pmon). Its working fine for all the database and throwing alerts whenever any database goes down for more than 8min.
On Friday 23 Dec 11 at 4:37pm in one particular database server the database lgwr process was killed and database was restarted. Database came up at 4:48 pm. The database was down for 11 mins and still there is no alert in nagios.

Can you please help to analyze this issue. Kindly let me know if you need further information.

script name : check_db_pmon
#!/usr/bin/sh
#Plugin to check the Proces
count=ps -ef |grep ora_pmon |grep -v 'grep' | wc -l
if $count -eq 0 ] ;
then
echo "CRITICAL : pmon is NOT Running"
exit 2
else
echo "OK: pmon is Running"
exit 0
fi

normal_check_interval - 5min
retry_check_interval - 1min
max_check_attempts -3

Attached is the issue with database.

Dear all,

Please help me to solve this issue.

thanks,
chim