Shell script not running via crontab, but runs fine manually

Question

I have a script that checks if pptp vpn is running , and if not it reconnect the pptp vpn , when i run the script manually it execute fine , when i do set a cron job , is no

Answer 1

If you're positive the script runs outside of cron, execute

printf "SHELL=$SHELL\nPATH=$PATH\n* * * * * /bin/bash /var/scripts/vpn-check.sh\n"

Do crontab -e for whichever crontab you're using and replace it with output of the above command. This should mirror most of your environment in case there is some missing path issue or something else. Also check logs for any errors it's getting.

Though it definitly looks like the script has an error or you messed something up when copying it here

sed: -e expression #1, char 44: unterminated `s' command
./bad.sh: 5: ./bad.sh: [[: not found

Simple alternate script

#!/bin/bash

if [[ $(ping -c3 192.168.17.27) == *"0 received"* ]]; then
  /usr/sbin/pppd call home
fi

Answer 2

As a complement of other's answers, didn't you forget the username in your crontab script ?

Try this :

* * * * * root /bin/bash /var/scripts/vpn-check.sh

EDIT

Here is a patch of your code

#!/bin/sh
/bin/ping -c3 192.168.17.27  > /tmp/pingreport
result=`grep "0 received" /tmp/pingreport`
truncresult=`echo "$result" | /bin/sed 's/^\(.................................\).*$/\1/'`
if [[ $truncresult == "3 packets transmitted, 0 received" ]]; then
    /usr/sbin/pppd call home
fi