Question

I have created following command line to run cron job after every 2minutes

 2 * * * *  php -f /home/u260451427/public_html/cron/cron_sms_sending_queue.php

my sever configuration look something like that

but its not working.

Answer 1

2 * * * * <command> will run every 2nd minute past every hour.

From ‘man 5 cron’:

Step values can be used in conjunction with ranges...
Steps are also permitted after an asterisk, so if you 
want to say ``every two hours'', just use */2

Therefore your crontab entry should be

*/2 * * * * <command>