This example configures on the environment bellow:

• Domain name : SMB01
• Realm : SRV.SHAREWIZ
• Hostname : smb.srv.sharewiz

Install required packages

sudo apt install samba krb5-config winbind smbclient

and answer:

# set Realm
 
 +------------------+ Configuring Kerberos Authentication +------------------+
 | When users attempt to use Kerberos and specify a principal or user name   |
 | without specifying what administrative Kerberos realm that principal      |
 | belongs to, the system appends the default realm.  The default realm may  |
 | also be used as the realm of a Kerberos service running on the local      |
 | machine.  Often, the default realm is the uppercase version of the local  |
 | DNS domain.                                                               |
 |                                                                           |
 | Default Kerberos version 5 realm:                                         |
 |                                                                           |
 | SRV.SHAREWIZ_____________________________________________________________ |
 |                                                                           |
 |                                  <Ok>                                     |
 |                                                                           |
 +---------------------------------------------------------------------------+
 
# specify the hostname
 
 +------------------+ Configuring Kerberos Authentication +------------------+
 | Enter the hostnames of Kerberos servers in the SRV.SHAREWIZ Kerberos      |
 | realm separated by spaces.                                                |
 |                                                                           |
 | Kerberos servers for your realm:                                          |
 |                                                                           |
 | smb.srv.sharewiz_________________________________________________________ |
 |                                                                           |
 |                                  <Ok>                                     |
 |                                                                           |
 +---------------------------------------------------------------------------+
 
 
# specify the hostname
 
 +------------------+ Configuring Kerberos Authentication +------------------+
 | Enter the hostname of the administrative (password changing) server for   |
 | the SRV.SHAREWIZ Kerberos realm.                                          |
 |                                                                           |
 | Administrative server for your Kerberos realm:                            |
 |                                                                           |
 | smb.srv.sharewiz_________________________________________________________ |
 |                                                                           |
 |                                  <Ok>                                     |
 |                                                                           |
 +---------------------------------------------------------------------------+

Rename or remove the default config.

sudo mv /etc/samba/smb.conf /etc/samba/smb.conf.org

samba-tool domain provision

and

# specify Realm
Realm [SRV.SHAREWIZ]: 
# specify Domain name
 Domain [SRV]: SMB01 
# Enter with default because it sets DC
 Server Role (dc, member, standalone) [dc]:
# Enter with default because it uses Built-in DNS
 DNS backend (SAMBA_INTERNAL, BIND9_FLATFILE, BIND9_DLZ, NONE) [SAMBA_INTERNAL]:
# if you set DNS forwarder, specify it, if not, specify [none]
 DNS forwarder IP address (write 'none' to disable forwarding) [127.0.0.53]: 192.168.1.8
# set admin password
# Do not set trivial password, if you input it, configuration wizard shows error and stops
Administrator password:
Retype password:
Looking up IPv4 addresses
Looking up IPv6 addresses
No IPv6 address will be assigned
Setting up share.ldb
Setting up secrets.ldb
Setting up the registry
Setting up the privileges database
Setting up idmap db
Setting up SAM db
Setting up sam.ldb partitions and settings
Setting up sam.ldb rootDSE
Pre-loading the Samba 4 and AD schema
Adding DomainDN: DC=srv,DC=sharewiz
Adding configuration container
Setting up sam.ldb schema
Setting up sam.ldb configuration data
Setting up display specifiers
Modifying display specifiers
Adding users container
Modifying users container
Adding computers container
Modifying computers container
Setting up sam.ldb data
Setting up well known security principals
Setting up sam.ldb users and groups
Setting up self join
Adding DNS accounts
Creating CN=MicrosoftDNS,CN=System,DC=srv,DC=sharewiz
Creating DomainDnsZones and ForestDnsZones partitions
Populating DomainDnsZones and ForestDnsZones partitions
Setting up sam.ldb rootDSE marking as synchronized
Fixing provision GUIDs
A Kerberos configuration suitable for Samba AD has been generated at /var/lib/samba/private/krb5.conf
Once the above files are installed, your Samba AD server will be ready to use
Server Role:           active directory domain controller
Hostname:              smb
NetBIOS Domain:        SMB01
DNS Domain:            srv.sharewiz
DOMAIN SID:            S-1-5-21-1186834725-214749683-942878845

Copy krb file.

sudo cp /var/lib/samba/private/krb5.conf /etc/

Setup service which need to run.

sudo systemctl stop smbd nmbd winbind systemd-resolved
 
sudo systemctl disable smbd nmbd winbind systemd-resolved
 
sudo systemctl unmask samba-ad-dc
Removed /etc/systemd/system/samba-ad-dc.service.

Rmove the link of resolv.conf and create new one

sudo ll /etc/resolv.conf
 
lrwxrwxrwx 1 root root 39 Apr 27 10:30 /etc/resolv.conf -> ../run/systemd/resolve/stub-resolv.conf
 
sudo rm /etc/resolv.conf
 
vi /etc/resolv.conf

Replace the domain name to your own environment:

/etc/resolv.conf

domain srv.sharewiz
nameserver 127.0.0.1

Start Samba DC

sudo systemctl start samba-ad-dc
 
sudo systemctl enable samba-ad-dc 

sudo samba-tool domain level show
 
Domain and forest function level for domain 'DC=srv,DC=sharewiz'
 
Forest function level: (Windows) 2008 R2
Domain function level: (Windows) 2008 R2
Lowest function level of a DC: (Windows) 2008 R2

sudo samba-tool user create testuser
 
New Password:   # set password
 
Retype Password:
User 'testuser' created successfully