ACL не может быть установлен на сервере Ubuntu

Команды setfacl/getfacl, не запущенные на моем сервере, говорят:

The program 'setfacl' is currently not installed. You can install it by typing:
sudo apt-get install acl

когда я пытался установить его, он говорит:

sudo apt-get install acl

Reading package lists... Done
Building dependency tree       
Reading state information... Done
Package acl is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'acl' has no installation candidate