yum -y install realmd sssd oddjob oddjob-mkhomedir adcli samba-common

# change the DNS to AD's one

[root@dlp ~]# nmcli c modify ens3 ipv4.dns 10.1.1.5

[root@dlp ~]# nmcli c down ens3; nmcli c up ens3
Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/1)

# discover Active Directory domain
[root@dlp ~]# realm discover POLI01AD01.LOCAL

srv.world
type: kerberos
realm-name: POLI01AD01.LOCAL
domain-name: POLI01AD01.LOCAL
configured: no
server-software: active-directory
client-software: sssd
required-package: oddjob
required-package: oddjob-mkhomedir
required-package: sssd
required-package: adcli
required-package: samba-common

# join in Active Directory domain
[root@dlp ~]# realm join POLI01AD01.LOCAL
Password for Administrator:
# AD's Administrator password

# make sure it's possible to get an AD user info or not
[root@dlp ~]# id poli01srv01.poli01ad01.local\\Serverworld
uid=406801001(POLI01SRV01@POLI01AD01.LOCAL) gid=406800513(domain users@srv.world) groups=406800513(domain users@srv.world)

# make sure it's possible to switch to an AD user or not
[root@dlp ~]# su - poli01srv01.poli01ad01.local\\Serverworld
Creating home directory for serverworld@srv.world.
[serverworld@srv.world@dlp ~]$     # just switched

[root@dlp ~]# vi /etc/sssd/sssd.conf
# line 16: change

use_fully_qualified_names = False
[root@dlp ~]# systemctl restart sssd

[root@dlp ~]# id Administrator
uid=406800500(administrator) gid=406800513(domain users) groups=406800513(domain users),
406800572(denied rodc password replication group),406800518(schema admins),
406800520(group policy creator owners),406800512(domain admins),406800519(enterprise admins)