Anyone knows why `atd` is `masked` in Ubuntu 21.10? Is it a bug or a feature?

cn flag

I have recently upgraded from Ubuntu Server 20.04.3 to 21.10 and have just noticed atd process is marked as masked.

Is that intended or should it be unmasked?

$ systemctl status atd
○ atd.service
     Loaded: masked (Reason: Unit atd.service is masked.)
     Active: inactive (dead)
cn flag

The at package moved from -main to -universe after 20.04. It's no longer part of a stock Ubuntu install.

Services may be masked if the corresponding application is not installed.

So check that you have the package installed: apt list at


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