Introduction
In this tutorial we learn how to install at on CentOS 8.
What is at
At and batch read commands from standard input or from a specified file. At allows you to specify that a command will be run at a particular time. Batch will execute commands when the system load levels drop to a particular level. Both commands use user’s shell. You should install the at package if you need a utility for time-oriented job control. Note need to be repeated at the same time every day/week, etc. you should use crontab instead.
We can use yum or dnf to install at on CentOS 8. In this tutorial we discuss both methods but you only need to choose one of method to install at.
Install at on CentOS 8 Using dnf
Update yum database with dnf using the following command.
sudo dnf makecache --refresh
The output should look something like this:
CentOS Linux 8 - AppStream 43 kB/s | 4.3 kB 00:00
CentOS Linux 8 - BaseOS 65 kB/s | 3.9 kB 00:00
CentOS Linux 8 - ContinuousRelease 43 kB/s | 3.0 kB 00:00
CentOS Linux 8 - Extras 23 kB/s | 1.5 kB 00:00
CentOS Linux 8 - FastTrack 40 kB/s | 3.0 kB 00:00
CentOS Linux 8 - HighAvailability 36 kB/s | 3.9 kB 00:00
CentOS Linux 8 - Plus 24 kB/s | 1.5 kB 00:00
CentOS Linux 8 - PowerTools 50 kB/s | 4.3 kB 00:00
Extra Packages for Enterprise Linux Modular 8 - x86_64 13 kB/s | 9.2 kB 00:00
Extra Packages for Enterprise Linux 8 - x86_64 24 kB/s | 8.5 kB 00:00
Metadata cache created.
After updating yum database, We can install at using dnf by running the following command:
sudo dnf -y install at
Install at on CentOS 8 Using yum
Update yum database with yum using the following command.
sudo yum makecache --refresh
The output should look something like this:
CentOS Linux 8 - AppStream 43 kB/s | 4.3 kB 00:00
CentOS Linux 8 - BaseOS 65 kB/s | 3.9 kB 00:00
CentOS Linux 8 - ContinuousRelease 43 kB/s | 3.0 kB 00:00
CentOS Linux 8 - Extras 23 kB/s | 1.5 kB 00:00
CentOS Linux 8 - FastTrack 40 kB/s | 3.0 kB 00:00
CentOS Linux 8 - HighAvailability 36 kB/s | 3.9 kB 00:00
CentOS Linux 8 - Plus 24 kB/s | 1.5 kB 00:00
CentOS Linux 8 - PowerTools 50 kB/s | 4.3 kB 00:00
Extra Packages for Enterprise Linux Modular 8 - x86_64 13 kB/s | 9.2 kB 00:00
Extra Packages for Enterprise Linux 8 - x86_64 24 kB/s | 8.5 kB 00:00
Metadata cache created.
After updating yum database, We can install at using yum by running the following command:
sudo yum -y install at
How To Uninstall at on CentOS 8
To uninstall only the at package we can use the following command:
sudo dnf remove at
at Package Contents on CentOS 8
/etc/at.deny
/etc/pam.d/atd
/etc/sysconfig/atd
/usr/bin/at
/usr/bin/atq
/usr/bin/atrm
/usr/bin/batch
/usr/lib/.build-id
/usr/lib/.build-id/5b
/usr/lib/.build-id/5b/62f43486550b03dd4fc8620421cdb5a191ddcf
/usr/lib/.build-id/83
/usr/lib/.build-id/83/49b3653cd2bee7e0d8c391862f7c0dd2de32c9
/usr/lib/systemd/system/atd.service
/usr/sbin/atd
/usr/sbin/atrun
/usr/share/doc/at
/usr/share/doc/at/ChangeLog
/usr/share/doc/at/README
/usr/share/doc/at/timespec
/usr/share/licenses/at
/usr/share/licenses/at/COPYING
/usr/share/licenses/at/Copyright
/usr/share/man/man1/at.1.gz
/usr/share/man/man1/atq.1.gz
/usr/share/man/man1/atrm.1.gz
/usr/share/man/man1/batch.1.gz
/usr/share/man/man5/at.allow.5.gz
/usr/share/man/man5/at.deny.5.gz
/usr/share/man/man8/atd.8.gz
/usr/share/man/man8/atrun.8.gz
/var/spool/at
/var/spool/at/.SEQ
/var/spool/at/spool
References
Summary
In this tutorial we learn how to install at on CentOS 8 using yum and dnf.
