Using ACLs to Allow Collaboration
Published 2025-04-24
Location Online
Duration 30mACLs allow more granularity than octal permissions do. In this hands-on lab, we'll set up a collaboration area using ACLs to get some practice reading `getfacl` output and creating `setfacl` input.
Challenge
Use ACLs to Ensure Users Can Collaborate in the /opt/collab Directory
The first thing we need to do is make sure Bob, Adam, and Sally are all members of the same group. This will allow us to use ACLs on the group to allow access.
If we run id bob, id adam, and id sally we'll see that they're all members of the managers group.
We can run setfacl -m g:managers:rwx /opt/collab to allow the managers group access to the directory.
Challenge
Remove Adam's Access to the /opt/collab Directory
Since we can't remove him from the group, we can use ACLs to remove an individual user's access.
We can run setfacl -m u:adam:0 /opt/collab and it will make sure that adam cannot access the directory.
