atd command in Linux platform is basically the ‘at’ daemon which runs in background and executes command at a specific time. It’s like cron, however the only difference is, atd runs the command only for once. With the usage of atd, one can schedule both one-off commands and scripts easily at a specified time.
How to install atd in Linux distros
In order to work with atd, it’s required to install it on machine and its installation commands are different in various Linux distributions. So, read through the commands used to install atd in various Linux platforms.
For Debian/Ubuntu/Mint
sudo apt install at
For Fedora
sudo dnf install at
For CentOS/RHEL
sudo yum install at
For OpenSUSE
sudo zypper install at
For Arch/Manjero
sudo pacman -S at
Syntax to use atd command in Linux
atd [-l load_avg] [-b batch_interval] [-d] [-f] [-s]
Available options to use with atd command
-l: Used for specifying a limiting load factor, means, the batch jobs should not be run over that.
-b: Used for specifying the minimum interval in seconds between the start of two batch jobs.
-d: Used for debugging and printing error messages to standard error. Also, this option implies -f option.
-f : Used for running atd command in foreground.
-s: Used for processing the at/batch queue for once. Mostly, this option is used for compatibility with old versions of at, atd-s that is equivalent to older atrun command.
How to start and enable atd
If you are going to work with atd, you first need to start and enable it. To do so, run the command below:
sudo systemctl start atd sudo systemctl enable atd
To start the atd automatically while the system boots, you can run the following command:
chkconfig atd on
Note: In case you receive error “Can’t open /var/run/atd.pid to signal atd. No atd running” while using atd command, it means you have not started it, and the above mentioned commands will help you.
How to stop/disable/restart/checking status of atd in Linux
To stop atd
service atd stop
To disable atd from starting at boot time
chkconfig atd off
To restart atd
service atd restart
To check status of atd
service atd status
Nishant Verma is a senior web developer who love to share his knowledge about Linux, SysAdmin, and more other web handlers. Currently, he loves to write as content contributor for ServoNode.