The *samba-dc* role installs Samba on the managed node and configures it
as an Active Directory Domain controller. A custom module,
`samba_domain` handles the provisioning using `samba-tool domain
provision` in an idempotent way.
The *kerberos* role configures the MIT Kerberos library. Specifically,
it creates `/etc/krb5.conf` and populates it with some basic default
options. It also creates the `/etc/krb5.conf.d` directory, into which
other roles can write additional configuration files.
The *base* role performs the basic tasks needed to manage a node using
Ansible. Specifically, it installs the necessary packages for
manipulating SELinux policy.
