It is important to DISABLE ALL default vendor accounts that you don't use on your system, some accounts exist by default even if you have not installed the related services on your server. This
should be checked after each upgrade or new software installation. Linux provides these accounts for various system activities, which you may not need if the services are not installed on your
server. If you do not need the accounts, remove them. The more accounts you have, the easier it is to access your system.
We assume you are using the Shadow password suite on your Linux system. If you are not, you should consider doing so, as it helps to tighten up security somewhat. This must already be set if
you've followed our instructions till now and selected under the Authentication Configuration the option to Enable Shadow Passwords see
Post Partitioning for more information.
To delete user on your system, use the command:
[root@deep] /# userdel username
To delete group on your system, use the command:
[root@deep] /# groupdel username
In future, if you intend to add or delete users, passwords, usergroups, or group files, you must unset the immutable bit on all those files or you will not be able to make your changes. Also if you intend to install an RPM program that will automatically add a new user to the different
immunized passwd and group files, then you will receive an error message during the install if you have not unset the immutable bit from those files.