The crontab is defined as
minute hour day month weekday command
Minute - Minutes after the hour (0-59).
Hour - 24-hour format (0-23).
Day - Day of the month (1-31).
Month - Month of the year (1-12).
Weekday - Day of the week. (0-6; the 0 refers to Sunday).
Ideally for you the echo command will execute at 1:11 am your system time.
you will see output in your file only at 1:11 am your system time.
Also u should place the echo command in crontab for *root* or some user who can write to /root/cron_test
In case you want to run cron just to test it you can modify the entry to look like :
* * * * * echo "cron has benn running" >> /root/cron_test
So that it executes at every minute.
Last but not the least if it still does not work please check if the crond is running.
If not please start it.
You can check if crond is running by running :
ps -ef |grep cron
.... Nitin Batta ....
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