Disable the eMail Alert By Crontab Command On a Linux or Unix-like Systems

How do I to disable the email alert send by crontab? When my job is executed and the jobs cannot run normally it will sent an email to root. Why do I receive e-mails to my root account from cron? How can I prevent this? How can I disable email alert sent by cron jobs on a Linux or Unix-like systems?

The crontab command is used to maintain crontab files for individual users. By default the output of a command or a script (if any produced), will be email to your local email account. To stop receiving email output from crontab you need to append following strings at the end of crontab entry.

Tutorial details
Difficulty level	Easy
Root privileges	No
Requirements	Linux or Unix OS
Est. reading time	2 minutes

Cron job prevent the sending of errors and output

To prevent the sending of errors and output, add any one of the following at the end of the line for each cron job to redirect output to /dev/null.
>/dev/null 2>&1
> /dev/null
> /dev/null 2>&1 || true
## send cron output to a log file ##
> /var/log/my.app.log 2>&1
This will prevent mail command spam when you type the mail command:
$ mail

Cron job example to disable the email alert

Edit/Open your cron jobs, enter:
$ crontab -e
Append string >/dev/null 2>&1 to stop mail alert:

0 1 5 10 * /path/to/script.sh >/dev/null 2>&1

OR

0 1 5 10 * /path/to/script.sh > /dev/null

OR

0 * * * * /path/to/command arg1 > /dev/null 2>&1 || true

In this example, just redirect output to /dev/null only:
0 30 * * * /root/bin/check-system-health.py > /dev/null
We can use the following syntax when using bash to redirect both stdout and stderr:
command
1 30 * * * /root/bin/xyz-job &> /path/to/xyz.app.log.file
## Append instead of overwriting the log file ##
1 30 * * * /root/bin/xyz-job &>> /path/to/xyz.app.log.file
2 45 * * * /root/bin/foo-job &> /dev/null
Save and close the file. See redirect STDOUT and STDERR to null and “BASH Shell Redirect stderr To stdout ( redirect stderr to a File )” to suppress output for more information

Set MAILTO variable to stop cron daemon from sending email

Another option is to set MAILTO="" variable at the start of your crontab file or shell script. This will also disable email alert. Edit/Open your cron jobs:
$ crontab -e
At the top of the file, enter:
MAILTO=""
Of course we can redirect email too provided that email server such as Postfix configured:
MAILTO="admin@server1.cyberciti.biz"
Save and close the file. We can mix them as per our needs. For example:

## send email to backup team #
MAILTO="backup.admin@domain-here"
@daily /scripts/backup.sh 

## send email to RAID/storage/san/nas admin ##
MAILTO="storage.admin@domain-here"
* 45 * * * /scripts/test-raid-array.sh 

Another example:

## NO EMAIL ##
@weekly /scripts/containers-backup  >/dev/null 2>&1

## Send email ##
MAILTO="sysadmin@corp2.domain-here"
@daily /scripts/test-raid-array.sh 

## Disable email alert ##
MAILTO=""
@monthly /path/to/script/logs.sh > /var/log/monthly.log

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