Birmingham mumbai

[
 76 
]
Another command worth knowing is the 
chgrp
 command, which allows you to 
directly change the group ownership of a file. To use it, you can execute the 
chgrp
 
command along with the group you'd like to own the file, followed by the username. 
For example, our previous 
chown
 command can be simplified to the following, since 
we were only modifying the group assignment of that file:
#
 sudo chgrp sales myfile.txt
Well, there you have it. You should now be able to manage permissions of the files 
and directories on your server. If you haven't worked through permissions on a 
Linux system before, it may take a few tries before you get the hang of it. The best 
thing for you to do is to practice. Create some files and directories (as well as users) 
and manage their permissions. Try to remove a user's access to a resource and then 
try to access that resource as that user anyway and see what errors you get. Fix those 
errors and work through more examples. With practice, you should be able to get a 
handle on this very quickly.
Summary
In Linux administration and related fields, managing users and permissions 
is something you'll find yourself doing quite a bit. New users will join your 
organization, while others will leave, so this is something that will become ingrained 
in your mental toolset. Even if you're the only person using your servers, you'll find 
yourself managing permissions for applications as well, given the fact that processes 
cannot function if they don't have access to their required resources.
In this chapter, we took a lengthy dive into managing users, groups, and 
permissions. We worked through creating and removing users, assigning 
permissions, and managing administrative access with 
sudo
. Practice these concepts 
on your server. When you get the hang of it, I'll see you in our next chapter, where 
we'll discuss all things related to package management. It's going to be epic.
Further reading
•  User management (Ubuntu documentation): 
https://ubuntu.com/server/
docs/security-users
.
•  File permissions (Ubuntu community wiki): 
https://help.ubuntu.com/
community/FilePermissions
.
Just like the 
chown
 command, we can use the 
-R
 option with 
chgrp
 
to make our changes recursively, in the case of a directory.

---