Invoke a Bash Script and End , Instead of Restarting again

I am running a Bash Script via Cron Job on my server and i need to invoke and end it self.

Script :

#!/bin/bash

while [ true ]
        do
        DATE=`date "+%d.%m.%Y. %H:%M"`
        MSG='STUFF HERE'
        test=`/usr/sbin/asterisk -rx "sip show peers" | grep UNKNOWN `
        if [ -z "$test" ]; then
        sleep 100
        else
        top=`top -bn1 | tail`
echo -e "$test" | mail -r "[e-mail]" -s  "SIP Peer UNKNOWN/UNSPECIFIED `hostname` $DATE" [e-mail] 
       sleep 900
        fi
done

I need it to not reset on its own i will call the script thru cron when ever I want.

Thanks

Answer

When you call it with cron, cron must take care of the looping.
Remove the while and sleep. You want to sleep longer when a warning has been mailed, this should be managed outside your detection code. Later on you will be monitoring a lot more, sending mails to different persons only during working hours, and perhaps using other things than mail as well.