Setting up Samba as an Active Directory Domain Controller: Difference between revisions
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= Introduction = |
= Introduction = |
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Starting from version 4.0, Samba is able to run as an Active Directory (AD) domain controller (DC). If you are installing Samba in a production environment, it is recommended to run two or more DCs for failover reasons. |
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Since version 4.0, Samba can also act as a Domain Controller that is compatible with Microsoft Active Directory. This document explains how to set up Samba as an Active Directory Domain Controller. It also is the start for upgrading an existing Samba NT4-style domain to Samba AD. |
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This documentation describes how to set up Samba as the first DC to build a new AD forest. Additionally, use this documentation if you are migrating a Samba NT4 domain to Samba AD. To join Samba as an additional DC to an existing AD forest, see [[Joining_a_Samba_DC_to_an_Existing_Active_Directory|Joining a Samba DC to an Existing Active Directory]]. |
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If you are upgrading an existing Samba Active Directory Domain Controller, please consult your distribution upgrade procedure or refer to the [[Updating_Samba|Updating Samba]] HowTo. |
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Samba as an AD DC only supports: |
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'''We <u>do not recommend</u> using the Domain Controller as a file Server'''. The recommendation is to run separate file or [[Setup_a_Samba_AD_Member_Server|Member Servers]]. |
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* the integrated LDAP server as AD back end. For details, see the frequently asked question (FAQ) [[FAQ#Does_Samba_AD_DCs_Support_OpenLDAP_or_Other_LDAP_Servers_as_Back_End.3F|Does Samba AD DCs Support OpenLDAP or Other LDAP Servers as Back End?]] |
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* the [https://web.mit.edu/kerberos/ MIT] and [http://www.h5l.se/ Heimdal] Kerberos Key Distribution Center (KDC). |
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: Samba uses the MIT KDC provided by your operating system if you run Samba 4.7 or later and has been built using the <code>--with-system-mitkrb5</code> option. In other cases Samba uses the Heimdal KDC included in Samba. For further details about Samba using the MIT KDC, see [[Running a Samba AD DC with MIT Kerberos KDC]]. |
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Whilst the Domain Controller seems capable of running as a full file server, it is suggested that organisations run a distinct file server to allow upgrades of each without disrupting the other. It is also suggested that medium-sized sites should run more than one DC. It also makes sense to have the DC's distinct from any file servers that may use the Domain Controllers. Also using distinct file Servers avoids the idiosyncrasies in the winbindd configuration on to the Active Directory Domain Controller. |
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= Versions = |
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Samba as an Active Directory Domain Controller requires at least version 4.0.0. But it's always <u>recommended to use the latest stable version</u> of Samba. It will contain fixes for bugs of previous releases and may contain improved Microsoft Active Directory compatibility and additional features. See the [[Samba_Release_Planning|Samba Release Planning]] page for more details about the latest maintained versions and their Release Notes. |
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= Server Information = |
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= Preparing the Installation = |
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Below, we will be using the following configuration/settings: |
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* Select a host name for your AD DC. |
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Installation Directory: /usr/local/samba/ |
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: Do not use NT4-only terms as host name, such as <code>PDC</code> or <code>BDC</code>. These modes do not exist in an AD and cause confusion. |
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AD DC Hostname: DC1 |
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AD DNS Domain Name: samdom.example.com |
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Kerberos Realm: SAMDOM.EXAMPLE.COM |
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NT4 Domain Name/NetBIOS Name: SAMDOM |
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IP Address: 192.168.1.1 |
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Server Role: Domain Controller (DC) |
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Domain Admin Password: passw0rd |
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Forwarder DNS Server: 192.168.1.254 |
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* Select a DNS domain for your AD forest. The name will also be used as the AD Kerberos realm. |
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= Installation = |
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: {{Imbox |
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| type = important |
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| text = Make sure that you provision the AD using a DNS domain that will not need to be changed. Samba does not support renaming the AD DNS zone and Kerberos realm. |
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}} |
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: For additional information, see [[Active_Directory_Naming_FAQ|Active Directory Naming FAQ]]. |
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* Use a static IP address on the DC. |
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== Different Ways To Install == |
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* Disable tools, such as <code>resolvconf</code>, that automatically update your <code>/etc/resolv.conf</code> DNS resolver configuration file. AD DCs and domain members must use an DNS server that is able to resolve the AD DNS zones. |
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'''Always check the [[Operating system requirements|OS Requirements]] for dependencies and recommendations.''' |
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'''Samba has its own LDAP and Kerberos implementation, using external LDAP and Kerberos server is not recommended.''' |
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* Verify that no Samba processes are running: |
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# ps ax | egrep "samba|smbd|nmbd|winbindd" |
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: If the output lists any <code>samba</code>, <code>smbd</code>, <code>nmbd</code>, or <code>winbindd</code> processes, shut down the processes. |
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* Verify that the <code>/etc/hosts</code> file on the DC correctly resolves the fully-qualified domain name (FQDN) and short host name to the LAN IP address of the DC. For example: |
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You have a few options to install Samba: |
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127.0.0.1 localhost localhost.localdomain |
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10.99.0.1 DC1.samdom.example.com DC1 |
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:The host name and FQDN must not resolve to the <code>127.0.0.1</code> IP address or any other IP address than the one used on the LAN interface of the DC. |
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* If you previously ran a Samba installation on this host: |
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* [[Build_Samba_from_source|Build Samba]] yourself. |
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:* Remove the existing <code>smb.conf</code> file. To list the path to the file: |
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# smbd -b | grep "CONFIGFILE" |
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* Install [[Distribution_specific_package_installation|binary distribution packages]]. Make sure, that you use a recent Samba installation with Active Directory Domain Controller capabilities! At the moment this means that you cannot setup an AD DC on RHEL systems (Fedora, Centos etc) using system packages, this is due to a conflict between the Heimdal kerberos that Samba uses and the Mit kerberos used by RHEL. |
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CONFIGFILE: /usr/local/samba/etc/samba/smb.conf |
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:* Remove all Samba database files, such as <code>*.tdb</code> and <code>*.ldb</code> files. To list the folders containing Samba databases: |
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:* Install from [http://www.enterprisesamba.com/samba/ SerNet Enterprise Samba] package. |
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# smbd -b | egrep "LOCKDIR|STATEDIR|CACHEDIR|PRIVATE_DIR" |
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== Paths == |
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LOCKDIR: /usr/local/samba/var/lock/ |
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STATEDIR: /usr/local/samba/var/locks/ |
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CACHEDIR: /usr/local/samba/var/cache/ |
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PRIVATE_DIR: /usr/local/samba/private/ |
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: Starting with a clean environment helps to prevent confusion and ensures that no files from any previous Samba installation will be mixed with your new domain DC installation. |
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Take care when running Samba commands if you also have a previous version of Samba installed! To avoid inadvertently running the wrong version of a program, you should consider putting the „/usr/local/samba/bin/“ and „/usr/local/samba/sbin/“ directories at the <u>beginning of your $PATH variable</u>. |
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* Remove an existing <code>/etc/krb5.conf</code> file: |
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# rm /etc/krb5.conf |
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You can see what version of Samba and client tools, if any, is in your „$PATH“ variable by running: |
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# '''samba -V''' |
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# '''smbclient -V''' |
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= Installing Samba = |
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For details, see [[Installing_Samba|Installing Samba]]. |
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= Provisioning The Samba Active Directory = |
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{{Imbox |
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'''''Note (Migration):''' If you plan to migrate an existing Samba NT4 domain to Samba AD, you do not manually provision the domain! See the [[Samba_Classic_Upgrade_(NT4-style_domain_to_AD)|Samba Classic Upgrade]] HowTo, instead.'' |
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| type = note |
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| text = Only install a maintained Samba version. For details, see [[Samba_Release_Planning|Samba Release Planning]]. |
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}} |
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'''''Note (Adding additional Domain Controllers):''' If you already have an Active Directory and only want to join a new, additional Samba Domain Controller, you do not provision the domain again! See the [[Join_a_domain_as_a_DC|Join a domain as a DC]] HowTo, instead.'' |
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'''''<u>Selecting what DNS name to use:</u>''' See [[DNS#Selecting_the_Forest_Root_Domain|Selecting the Forest Root Domain]] for further information and best practice and [[DNS#Avoid_.local_TLD|avoid .local domains]].'' |
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= Provisioning a Samba Active Directory = |
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When Samba sets up the first Domain Controller in a Domain, the provisioning creates an initial Active Directory database. Because of this, the provision command must be executed with root privileges, to be able to write to the installation directory and set the correct permissions on files and folders. |
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The Samba AD provisioning process creates the AD databases and adds initial records, such as the domain administrator account and required DNS entries. |
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If you are migrating a Samba NT4 domain to AD, skip this step and run the Samba classic upgrade. For details, see [[Migrating_a_Samba_NT4_Domain_to_Samba_AD_(Classic_Upgrade)|Migrating a Samba NT4 Domain to Samba AD (Classic Upgrade)]]. |
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Before you start the provisioning, make yourself familiar with the parameters and options of 'samba-tool': |
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{{Imbox |
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# '''samba-tool domain provision --help ''' |
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| type = note |
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| text = The AD provisioning requires root permissions to create files and set permissions. |
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}} |
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The <code>samba-tool domain provision</code> command provides several parameters to use with the interactive and non-interactive setup. For details, see: |
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If your future Domain Controller has multiple NICs, the following two options are required. This is because 'samba-tool' would auto-choose one of the IPv4/IPv6 addresses if multiple interfaces were found, therefore it is necessary to bind Samba to the desired interfaces using |
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# samba-tool domain provision --help |
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--option="interfaces=lo eth0" --option="bind interfaces only=yes" |
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{{Imbox |
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Interactively provision a new domain (parameter explanation below): |
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| type = note |
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| text = When provisioning a new AD, it is recommended to enable the NIS extensions by passing the <code>--use-rfc2307</code> parameter to the <code>samba-tool domain provision</code> command. This enables you to store Unix attributes in AD, such as user IDs (UID), home directories paths, group IDs (GID). Enabling the NIS extensions has no disadvantages. However, enabling them in an existing domain requires manually extending the AD schema. For further details about Unix attributes in AD, see: |
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* [[Setting_up_RFC2307_in_AD|Setting up RFC2307 in AD]] |
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* [[Idmap_config_ad|idmap config = ad]] |
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}} |
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# '''samba-tool domain provision --use-rfc2307 --interactive''' |
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Realm [SAMDOM.EXAMPLE.COM]: ''SAMDOM.EXAMPLE.COM'' |
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== Parameter Explanation == |
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Domain [SAMDOM]: ''SAMDOM'' |
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Server Role (dc, member, standalone) [dc]: ''dc'' |
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Set the following parameters during the provisioning: |
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DNS backend (SAMBA_INTERNAL, BIND9_FLATFILE, BIND9_DLZ, NONE) [SAMBA_INTERNAL]: ''SAMBA_INTERNAL'' |
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DNS forwarder IP address (write 'none' to disable forwarding) [192.168.1.1]: ''192.168.1.254'' |
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{| class="wikitable" |
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Administrator password: ''passw0rd'' |
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!Interactive Mode Setting |
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Retype password: ''passw0rd'' |
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!Non-interactive Mode Parameter |
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!Explanation |
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|- |
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|<code>--use-rfc2307</code> |
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|<code>--use-rfc2307</code> |
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|Enables the NIS extensions. |
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|- |
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|<code>Realm</code> |
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|<code>--realm</code> |
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|Kerberos realm. This is also used as the AD DNS domain. For example: <code>samdom.example.com</code>. |
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|- |
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|<code>Domain</code> |
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|<code>--domain</code> |
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|NetBIOS domain name. It is recommended to use the first part of the AD DNS domain. For example: <code>samdom</code>. |
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|- |
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|<code>Server Role</code> |
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|<code>--server-role</code> |
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|Installs the domain controller <code>DC</code> role. |
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|- |
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|<code>DNS backend</code> |
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|<code>--dns-backend</code> |
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|Sets the DNS back end. The first DC in an AD must be installed using a DNS back end. Note that the <code>BIND9_FLATFILE</code> is not supported and will be removed in a future Samba version. |
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|- |
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|<code>DNS forwarder IP address</code> |
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|not available |
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|This setting is only available when using the <code>SAMBA_INTERNAL</code> DNS back end. For details, see [[Samba_Internal_DNS_Back_End#Setting_up_a_DNS_Forwarder|Setting up a DNS Forwarder]]. |
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|- |
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|<code>Administrator password</code> |
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|<code>--adminpass</code> |
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|Sets the domain administrator password. If the password does not match the complexity requirements, the provisioning fails. For details, see [https://technet.microsoft.com/en-us/library/cc786468%28v=ws.10%29.aspx Microsoft TechNet: Passwords must meet complexity requirements]. |
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|} |
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Other parameters frequently used with the <code>samba-tool domain provision</code> command: |
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* <code>--option="interfaces=lo eth0" --option="bind interfaces only=yes"</code>: If your server has multiple network interfaces, use these options to bind Samba to the specified interfaces. This enables the <code>samba-tool</code> command to register the correct LAN IP address in the directory during the join. |
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{{Imbox |
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| type = note |
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| text = do NOT use <code>NONE</code> as the DNS backend, it is not supported and will be removed in a future Samba version. |
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}} |
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{{Imbox |
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| type = note |
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| text = If using Bind as the DNS backend, do NOT use <code>BIND9_FLATFILE</code>, it is not supported and will be removed in a future Samba version. |
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}} |
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{{Imbox |
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| type = important |
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| text = Once you have provisioned the first DC in an AD domain, do not provision any further DCs in the same domain, [[Joining_a_Samba_DC_to_an_Existing_Active_Directory|Join]] any further DCs. |
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}} |
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== Provisioning Samba AD in Interactive Mode == |
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To provision a Samba AD interactively, run: |
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# samba-tool domain provision --use-rfc2307 --interactive |
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Realm [SAMDOM.EXAMPLE.COM]: SAMDOM.EXAMPLE.COM |
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Domain [SAMDOM]: SAMDOM |
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Server Role (dc, member, standalone) [dc]: dc |
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DNS backend (SAMBA_INTERNAL, BIND9_FLATFILE, BIND9_DLZ, NONE) [SAMBA_INTERNAL]: SAMBA_INTERNAL |
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DNS forwarder IP address (write 'none' to disable forwarding) [10.99.0.1]: 8.8.8.8 |
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Administrator password: Passw0rd |
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Retype password: Passw0rd |
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Looking up IPv4 addresses |
Looking up IPv4 addresses |
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Looking up IPv6 addresses |
Looking up IPv6 addresses |
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Line 131: | Line 214: | ||
DOMAIN SID: S-1-5-21-2614513918-2685075268-614796884 |
DOMAIN SID: S-1-5-21-2614513918-2685075268-614796884 |
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{{Imbox |
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| type = note |
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| text = The interactive provisioning mode supports passing further parameters to the <code>samba-tool domain provision</code> command. This enables you to modify parameters that are not part of the interactive setup. |
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}} |
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<u>Parameter explanations:</u> |
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== Provisioning Samba AD in Non-interactive Mode == |
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<u>--use-rfc2307:</u> Enables the NIS extensions, they allow you to easily [[Using_RFC2307_on_a_Samba_DC#Administer_Unix_Attributes_in_Active_Directory|manage users/groups with the Windows tool Active Directory Users and Computers (ADUC)]], without manual counting UIDs/GIDs. It is recommended to enable this feature during the provisioning, there are no problems in not using it, but you may later find that it becomes a requirement and enabling it, means that you do not have to manually add the Schema extension later. For further information about RFC2307, see the [[Using_RFC2307_on_a_Samba_DC|Using RFC2307 on a Samba DC]] HowTo. |
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For example, to provision a Samba AD non-interactively with the following settings: |
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* Server role: <code>dc</code> |
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* NIS extensions enabled |
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* Internal DNS back end |
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* Kerberos realm and AD DNS zone: <code>samdom.example.com</code> |
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* NetBIOS domain name: <code>SAMDOM</code> |
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* Domain administrator password: <code>Passw0rd</code> |
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# samba-tool domain provision --server-role=dc --use-rfc2307 --dns-backend=SAMBA_INTERNAL --realm=SAMDOM.EXAMPLE.COM --domain=SAMDOM --adminpass=Passw0rd |
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<u>--interactive:</u> Use interactive provisioning. The defaults are the values in the squared brackets, they will be used if no input is made. |
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<u>Realm:</u> Kerberos Realm. It will automatically be used as the Active Directory DNS domain name, so it must be the same as the dns name of the machine you are provisioning on, it must always be entered in uppercase. |
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<u>Domain:</u> NT4/NetBIOS Domain Name. Usually the first part of the AD DNS domain name in uppercase, whatever you use, make sure it is just one word with no more than 15 characters, do not use '''any''' punctuation marks i.e. ! @ # $ % ^ & ( ) - _ ' { } . ~ |
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= Setting up the AD DNS back end = |
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Skip this step if you provisioned the DC using the <code>SAMBA_INTERNAL</code> DNS back end. |
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<u>Server Role:</u> 'dc' for Domain Controller, do not use anything else, none of the other options are working at present. |
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* Set up the BIND DNS server and the <code>BIND9_DLZ</code> module. For details, see [[Setting_up_a_BIND_DNS_Server|Setting up a BIND DNS Server]]. |
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* Start the BIND DNS server. For example: |
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<u>DNS backend:</u> You have decide here, whether to use the Internal DNS server or BIND9 as the DNS backend. The default is the Internal DNS and the best choice for simple DNS requirements and doesn't require any further action. For complex DNS requirements, BIND9_DLZ is recommended. Do not use BIND9_FLATFILE! It's not documented or supported! See [[DNS_Backend_BIND|DNS Backend BIND]] for further information about using BIND. The DNS backend choice made during the provisioning isn't permanent. [[Changing_the_DNS_backend|It can be changed afterwards]]. |
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# systemctl start named |
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: For details how to start services, see you distribution's documentation. |
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<u>DNS forwarder IP address:</u> You are only prompted for this if you chose the Internal DNS as the backend. It defines the IP address of one DNS server to which DNS queries should be forwarded to when your DNS server isn't authoritative. Commonly it is your providers DNS server IP address. |
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'''''Note:''' You should always use a subdomain of your domain name (e. g. samdom.example.com). Never use your domain name (example.com) for your Active Directory DNS domain, this is to stop problems when accessing servers using that name (e. g. web server), but resolving to different IPs other than your Domain Controllers!'' |
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= Configuring the DNS Resolver = |
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<u>Administrator password:</u> The Domain Administrators password. It must meet the complex password requirements: |
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* At least 8 characters |
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* Containing three of the following four character groups |
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** Uppercase letters |
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** Lowercase letters |
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** Numerals |
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** Symbols (all keyboard characters not defined as letters or numerals) |
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If the password doesn't fulfil the complexity requirements, the provisioning will fail and you will have to start over (remove the 'smb.conf'in that case). |
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Domain members in an AD use DNS to locate services, such as LDAP and Kerberos. For that, they need to use a DNS server that is able to resolve the AD DNS zone. |
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= Testing Your Samba Domain Controller = |
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On your DC, set the AD DNS domain in the <code>domain</code> and the IP of your DC in the <code>nameserver</code> parameter of the <code>/etc/resolv.conf</code> file. For example: |
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'''Note: If you are running any „smbd“, „nmbd“ or „winbindd“ processes from previous installations, they need to be stopped before starting „samba“ from your new installation!''' |
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search samdom.example.com |
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To start the Samba Active Directory Domain Controller in „standard“ mode, which is suitable for production use, run |
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nameserver 10.99.0.1 |
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# '''samba''' |
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Samba doesn't yet have init scripts included. You can find examples on the [[Samba4/InitScript|Samba Init-Script]] page. |
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= Create a reverse zone = |
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Run „smbclient“, to check if Samba provides the AD DC default shares „netlogon“ and „sysvol“ created in your „smb.conf“ during provisioning/upgrading: |
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You can optionally add a reverse lookup zone. |
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$ '''smbclient -L localhost -U%''' |
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Domain=[SAMDOM] OS=[Unix] Server=[Samba 4.x.y] |
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Sharename Type Comment |
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--------- ---- ------- |
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netlogon Disk |
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sysvol Disk |
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IPC$ IPC IPC Service (Samba 4.x.y) |
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Domain=[SAMDOM] OS=[Unix] Server=[Samba 4.x.y] |
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Server Comment |
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--------- ------- |
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Workgroup Master |
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--------- ------- |
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# samba-tool dns zonecreate <Your-AD-DNS-Server-IP-or-hostname> 0.99.10.in-addr.arpa |
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Password for [administrator@SAMDOM.EXAMPLE.COM]: |
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Zone 0.99.10.in-addr.arpa created successfully |
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If you need more than one reverse zone (multiple subnets), just run the above command again but with the data for the other subnet. |
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To test that authentication is working, you should try to connect to the „netlogon“ share, using the Domain Administrator account, created during provisioning: |
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The reverse zone is directly live without restarting Samba or BIND. |
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$ '''smbclient //localhost/netlogon -UAdministrator -c 'ls'''' |
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Enter Administrator's password: ''passw0rd'' |
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Domain=[SAMDOM] OS=[Unix] Server=[Samba 4.x.y] |
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. D 0 Sat Jul 5 08:40:00 2014 |
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.. D 0 Sat Jul 5 08:40:00 2014 |
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49386 blocks of size 524288. 42093 blocks available |
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If the tests fail, check out the [[Samba_AD_DC_Troubleshooting|Samba AD DC Troubleshooting]] page. |
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= Configuring Kerberos = |
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In an AD, Kerberos is used to authenticate users, machines, and services. |
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During the provisioning, Samba created a Kerberos configuration file for your DC. Copy this file to your operating system's Kerberos configuration. For example: |
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= Configure DNS = |
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# cp /usr/local/samba/private/krb5.conf /etc/krb5.conf |
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A working DNS is essential to the correct operation of Active Directory. E. g. without the right DNS entries, Kerberos won't work, which in turn means that many of the basic features won't work! It is worth spending some extra time ensuring your DNS setup is correct, as debugging problems caused by incorrect DNS configuration, can take a lot of time later. |
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{{Imbox |
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| type = important |
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| text = Do not create a symbolic link to the the generated <code>krb5.conf</code> file. In Samba 4.7 and later, the <code>/usr/local/samba/private/</code> directory is no longer accessible by other users than the <code>root</code> user. If the file is a symbolic link, other users are not able to read the file and, for example, dynamic DNS updates fail if you use the <code>BIND_DLZ</code> DNS back end. |
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}} |
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The pre-created Kerberos configuration uses DNS service (SRV) resource records to locate the KDC. |
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== DNS Backends == |
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For additional information on the supported DNS backends and as a decision aid to help choose which fits best to your needs, see the [[DNS#Which_DNS_backend_should_I_choose.3F|DNS]] page. |
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= Testing your Samba AD DC = |
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=== Samba Internal DNS Server === |
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To start the <code>samba</code> service manually, enter: |
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By default Samba uses its Internal DNS and no further configuration is required. The forwarder was already set during the provisioning and can be changed in your „smb.conf“ (reload of „samba“ is required after changes). |
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# samba |
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Samba does not provide System V init scripts, <code>systemd</code>, <code>upstart</code>, or other services configuration files. |
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* If you installed Samba using packages, use the script or service configuration file included in the package to start Samba. |
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* If you built Samba, see [[Managing_the_Samba_AD_DC_Service|Managing the Samba AD DC Service]]. |
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=== BIND9 DNS Backend === |
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If you chose „BIND9_DLZ“ during your provisioning, see the [[DNS_Backend_BIND|Bind as DNS backend]] documentation for additional setup instructions. |
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== Verifying the File Server == |
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To list all shares provided by the DC: |
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$ smbclient -L localhost -U% |
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== Configure /etc/resolv.conf == |
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Domain=[SAMDOM] OS=[Unix] Server=[Samba x.y.z] |
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Sharename Type Comment |
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--------- ---- ------- |
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netlogon Disk |
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sysvol Disk |
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IPC$ IPC IPC Service (Samba x.y.z) |
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Domain=[SAMDOM] OS=[Unix] Server=[Samba x.y.z] |
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Server Comment |
|||
--------- ------- |
|||
Workgroup Master |
|||
--------- ------- |
|||
{{Imbox |
|||
Your Domain Controller requires a name server that knows your AD zone to resolve Active Directory DNS queries correctly. To accomplish this, you can add just your AD DCs IP and domain name to your „/etc/resolv.conf“: |
|||
| type = note |
|||
| text = The <code>netlogon</code> and <code>sysvol</code> shares were auto-created during the provisioning and must exist on a DC. |
|||
}} |
|||
To verify authentication, connect to the <code>netlogon</code> share using the domain administrator account: |
|||
domain samdom.example.com |
|||
nameserver 192.168.1.1 |
|||
$ smbclient //localhost/netlogon -UAdministrator -c 'ls' |
|||
'''''Note:''' If your server is set up to receive its IP configuration via DHCP, the „/etc/resolv.conf“ file might be automatically updated. Refer to your distributions documentation on how to stop/change this behavior, although DHCP is not recommended on a DC!'' |
|||
Enter Administrator's password: |
|||
Domain=[SAMDOM] OS=[Unix] Server=[Samba x.y.z] |
|||
. D 0 Tue Nov 1 08:40:00 2016 |
|||
.. D 0 Tue Nov 1 08:40:00 2016 |
|||
49386 blocks of size 524288. 42093 blocks available |
|||
If one or more tests fail, see [[#Troubleshooting|Troubleshooting]]. |
|||
== Verifying DNS == |
|||
To verify that your AD DNS configuration works correctly, query some DNS records: |
|||
== Testing DNS == |
|||
* The tcp-based <code>_ldap</code> SRV record in the domain: |
|||
To test that DNS is working properly, run the following commands and compare the output to what is shown: |
|||
$ |
$ host -t SRV _ldap._tcp.samdom.example.com. |
||
_ldap._tcp.samdom.example.com has SRV record 0 100 389 dc1.samdom.example.com. |
_ldap._tcp.samdom.example.com has SRV record 0 100 389 dc1.samdom.example.com. |
||
* The udp-based <code>_kerberos</code> SRV resource record in the domain: |
|||
$ '''host -t SRV _kerberos._udp.samdom.example.com.''' |
|||
$ host -t SRV _kerberos._udp.samdom.example.com. |
|||
_kerberos._udp.samdom.example.com has SRV record 0 100 88 dc1.samdom.example.com. |
_kerberos._udp.samdom.example.com has SRV record 0 100 88 dc1.samdom.example.com. |
||
* The A record of the domain controller: |
|||
$ '''host -t A dc1.samdom.example.com.''' |
|||
dc1.samdom.example.com has address 192.168.1.1 |
|||
$ host -t A dc1.samdom.example.com. |
|||
dc1.samdom.example.com has address 10.99.0.1 |
|||
If one or more tests fail, see [[#Troubleshooting|Troubleshooting]]. |
|||
If you receive any errors, check your system logs to locate the problem. |
|||
== Verifying Kerberos == |
|||
* Request a Kerberos ticket for the domain administrator account: |
|||
$ kinit administrator |
|||
= Configure Kerberos = |
|||
Password for administrator@SAMDOM.EXAMPLE.COM: |
|||
: {{Imbox |
|||
Kerberos is an important part of Active Directory. Typically the configuration is done in /etc/krb5.conf. During provisioning, a working sample configuration will be created. You can replace your krb5.conf file with the sample by copying or creating a symlink: |
|||
| type = note |
|||
| text = The Kerberos realm is automatically appended, if you do not pass the principal in the <code>user@REALM</code> format to the <code>kinit</code> command.<br />Set Kerberos realms always in uppercase. |
|||
}} |
|||
* List the cached Kerberos tickets: |
|||
# '''ln -sf /usr/local/samba/private/krb5.conf /etc/krb5.conf''' |
|||
$ klist |
|||
Ticket cache: FILE:/tmp/krb5cc_0 |
|||
Default principal: administrator@SAMDOM.EXAMPLE.COM |
|||
Valid starting Expires Service principal |
|||
01.11.2016 08:45:00 12.11.2016 18:45:00 krbtgt/SAMDOM.EXAMPLE.COM@SAMDOM.EXAMPLE.COM |
|||
renew until 02.11.2016 08:44:59 |
|||
If one or more tests fail, see [[#Troubleshooting|Troubleshooting]]. |
|||
== Testing Kerberos == |
|||
Use „kinit“ to obtain a Kerberos ticket: |
|||
# '''kinit administrator@SAMDOM.EXAMPLE.COM''' |
|||
Password for administrator@SAMDOM.EXAMPLE.COM: |
|||
Warning: Your password will expire in 41 days on Sat Aug 16 21:41:28 2014 |
|||
'''''Note:''' You must specify your realm in uppercase letters!'' |
|||
= Configuring Time Synchronisation = |
|||
'''''Note:''' Depending on your distribution, „kinit“ may just return you to a prompt when successful.'' |
|||
Kerberos requires a synchronised time on all domain members. For further details and how to set up the <code>ntpd</code> service, see [[Time_Synchronisation|Time Synchronisation]]. |
|||
To verify that Kerberos is working and that you had received a ticket, run: |
|||
# '''klist''' |
|||
Ticket cache: FILE:/tmp/krb5cc_0 |
|||
Default principal: administrator@SAMDOM.EXAMPLE.COM |
|||
Valid starting Expires Service principal |
|||
07/05/14 23:20:17 07/06/14 09:20:17 krbtgt/SAMDOM.EXAMPLE.COM@SAMDOM.EXAMPLE.COM |
|||
renew until 07/06/14 23:20:15 |
|||
= Using the Domain Controller as a File Server = |
|||
Whilst the Samba AD DC is able to provide file shares, just like all other installation modes, the Samba team does not recommend using a DC as a file server for the following reasons: |
|||
* For anything but the smallest organisations, having more than one DC is a really good backup measure, and makes upgrades safer |
|||
= Configure NTP = |
|||
* It encourages upgrades of the DC to also be upgrades of the host OS every year or two, because there isn't complex data to transition or other services involved. |
|||
* This means upgrades can be done by installing fresh, and replicating in the changes, which is better tested in Samba, gains new features and avoids a number of lingering data corruption risks. |
|||
* The DC and file-server have different points at which an organisation would wish to upgrade. The needs for new features on the DC and file server come at different times. Currently the AD DC is evolving rapidly to gain features, whereas the fileserver, after over 20 years, is quite rightly more conservative. |
|||
* mandatory smb signing is enforced on the DC. |
|||
'''''Note:''' NTP is optional, but highly recommended!'' |
|||
If you do decide to use the Samba DC as a fileserver, please consider running a VM, on the DC, containing a separate Samba Unix domain member and use this instead. |
|||
Active Directory requires an accurate time synchronization between all participant machines for Kerberos to work properly. It's highly recommended to use NTP or another form of time synchronization on your Domain Controller! |
|||
If you must use the Samba DC as a fileserver, you should be aware that the auto-enabled <code>acl_xattr</code> virtual file system (VFS) object enables you to only configure shares with Windows access control lists (ACL). Running shares with POSIX ACLs on a Samba DC is not supported and will not work. |
|||
The [[Time_syncronisation|Time Synchronisation]] documentation will provide all neccessary information for configuring NTP on Domain Controllers, Member Servers and clients. |
|||
To provide network shares with the full capabilities of Samba, set up a Samba domain member with file shares. For details, see: |
|||
* [[Setting_up_Samba_as_a_Domain_Member|Setting up Samba as a Domain Member]] |
|||
* [[Samba_File_Serving|Samba File Serving]] |
|||
If you only have a small domain (small office, home network) and do not want to follow the Samba team's recommendation and use the DC additionally as a file server, configure Winbindd before you start setting up shares. For details, see [[Configuring_Winbindd_on_a_Samba_AD_DC|Configuring Winbindd on a Samba AD DC]]. |
|||
= Troubleshooting = |
|||
If you encounter any problems when using the documentation, see the [[Samba_AD_DC_Troubleshooting|Samba AD DC Troubleshooting]] page. |
|||
= Troubleshooting = |
|||
For further details, see [[Samba_AD_DC_Troubleshooting|Samba AD DC Troubleshooting]]. |
|||
= Further Documentation = |
|||
The Samba Wiki provides a lot of useful [[User_Documentation|documentation]] on administering your DC, ([[Backup and restore an Samba AD DC|backup and recovery]], [[Setup_and_configure_file_shares_with_Windows_ACLs|setup and configure file shares]], etc.), daily work ([[Joining_a_Windows_client_to_a_domain|join a Windows client to a Domain]], [[Installing_RSAT_on_Windows_for_AD_Management|installing RSAT on Windows for AD Management]], etc.) or [[Authenticating_other_services_against_AD|authenticating other services against AD]]. |
|||
See the [[User_Documentation|Samba Wiki user documentation]] for many other HowTos, tutorials and information. |
|||
= Further Samba-related Documentation = |
|||
See [[User_Documentation|User Documentation]]. |
|||
= Report Your Success/Failure! = |
|||
We would encourage you to report your successes and failures to the [mailto:samba@lists.samba.org samba] mailing list on https://lists.samba.org. |
|||
---- |
|||
Suggestions on improving the documentation has the same importance as reporting [https://bugzilla.samba.org/ Bugs] and complications. |
|||
[[Category:Domain Control]] |
|||
[[Category:Active Directory]] |
Revision as of 15:57, 17 August 2018
Introduction
Starting from version 4.0, Samba is able to run as an Active Directory (AD) domain controller (DC). If you are installing Samba in a production environment, it is recommended to run two or more DCs for failover reasons.
This documentation describes how to set up Samba as the first DC to build a new AD forest. Additionally, use this documentation if you are migrating a Samba NT4 domain to Samba AD. To join Samba as an additional DC to an existing AD forest, see Joining a Samba DC to an Existing Active Directory.
Samba as an AD DC only supports:
- the integrated LDAP server as AD back end. For details, see the frequently asked question (FAQ) Does Samba AD DCs Support OpenLDAP or Other LDAP Servers as Back End?
- the MIT and Heimdal Kerberos Key Distribution Center (KDC).
- Samba uses the MIT KDC provided by your operating system if you run Samba 4.7 or later and has been built using the
--with-system-mitkrb5
option. In other cases Samba uses the Heimdal KDC included in Samba. For further details about Samba using the MIT KDC, see Running a Samba AD DC with MIT Kerberos KDC.
Preparing the Installation
- Select a host name for your AD DC.
- Do not use NT4-only terms as host name, such as
PDC
orBDC
. These modes do not exist in an AD and cause confusion.
- Select a DNS domain for your AD forest. The name will also be used as the AD Kerberos realm.
Make sure that you provision the AD using a DNS domain that will not need to be changed. Samba does not support renaming the AD DNS zone and Kerberos realm. - For additional information, see Active Directory Naming FAQ.
- Use a static IP address on the DC.
- Disable tools, such as
resolvconf
, that automatically update your/etc/resolv.conf
DNS resolver configuration file. AD DCs and domain members must use an DNS server that is able to resolve the AD DNS zones.
- Verify that no Samba processes are running:
# ps ax | egrep "samba|smbd|nmbd|winbindd"
- If the output lists any
samba
,smbd
,nmbd
, orwinbindd
processes, shut down the processes.
- Verify that the
/etc/hosts
file on the DC correctly resolves the fully-qualified domain name (FQDN) and short host name to the LAN IP address of the DC. For example:
127.0.0.1 localhost localhost.localdomain 10.99.0.1 DC1.samdom.example.com DC1
- The host name and FQDN must not resolve to the
127.0.0.1
IP address or any other IP address than the one used on the LAN interface of the DC.
- If you previously ran a Samba installation on this host:
- Remove the existing
smb.conf
file. To list the path to the file:
- Remove the existing
# smbd -b | grep "CONFIGFILE" CONFIGFILE: /usr/local/samba/etc/samba/smb.conf
- Remove all Samba database files, such as
*.tdb
and*.ldb
files. To list the folders containing Samba databases:
- Remove all Samba database files, such as
# smbd -b | egrep "LOCKDIR|STATEDIR|CACHEDIR|PRIVATE_DIR" LOCKDIR: /usr/local/samba/var/lock/ STATEDIR: /usr/local/samba/var/locks/ CACHEDIR: /usr/local/samba/var/cache/ PRIVATE_DIR: /usr/local/samba/private/
- Starting with a clean environment helps to prevent confusion and ensures that no files from any previous Samba installation will be mixed with your new domain DC installation.
- Remove an existing
/etc/krb5.conf
file:
# rm /etc/krb5.conf
Installing Samba
For details, see Installing Samba.
![]() | Only install a maintained Samba version. For details, see Samba Release Planning. |
Provisioning a Samba Active Directory
The Samba AD provisioning process creates the AD databases and adds initial records, such as the domain administrator account and required DNS entries.
If you are migrating a Samba NT4 domain to AD, skip this step and run the Samba classic upgrade. For details, see Migrating a Samba NT4 Domain to Samba AD (Classic Upgrade).
![]() | The AD provisioning requires root permissions to create files and set permissions. |
The samba-tool domain provision
command provides several parameters to use with the interactive and non-interactive setup. For details, see:
# samba-tool domain provision --help
![]() | When provisioning a new AD, it is recommended to enable the NIS extensions by passing the --use-rfc2307 parameter to the samba-tool domain provision command. This enables you to store Unix attributes in AD, such as user IDs (UID), home directories paths, group IDs (GID). Enabling the NIS extensions has no disadvantages. However, enabling them in an existing domain requires manually extending the AD schema. For further details about Unix attributes in AD, see:
|
Parameter Explanation
Set the following parameters during the provisioning:
Interactive Mode Setting | Non-interactive Mode Parameter | Explanation |
---|---|---|
--use-rfc2307
|
--use-rfc2307
|
Enables the NIS extensions. |
Realm
|
--realm
|
Kerberos realm. This is also used as the AD DNS domain. For example: samdom.example.com .
|
Domain
|
--domain
|
NetBIOS domain name. It is recommended to use the first part of the AD DNS domain. For example: samdom .
|
Server Role
|
--server-role
|
Installs the domain controller DC role.
|
DNS backend
|
--dns-backend
|
Sets the DNS back end. The first DC in an AD must be installed using a DNS back end. Note that the BIND9_FLATFILE is not supported and will be removed in a future Samba version.
|
DNS forwarder IP address
|
not available | This setting is only available when using the SAMBA_INTERNAL DNS back end. For details, see Setting up a DNS Forwarder.
|
Administrator password
|
--adminpass
|
Sets the domain administrator password. If the password does not match the complexity requirements, the provisioning fails. For details, see Microsoft TechNet: Passwords must meet complexity requirements. |
Other parameters frequently used with the samba-tool domain provision
command:
--option="interfaces=lo eth0" --option="bind interfaces only=yes"
: If your server has multiple network interfaces, use these options to bind Samba to the specified interfaces. This enables thesamba-tool
command to register the correct LAN IP address in the directory during the join.
![]() | do NOT use NONE as the DNS backend, it is not supported and will be removed in a future Samba version. |
![]() | If using Bind as the DNS backend, do NOT use BIND9_FLATFILE , it is not supported and will be removed in a future Samba version. |
![]() | Once you have provisioned the first DC in an AD domain, do not provision any further DCs in the same domain, Join any further DCs. |
Provisioning Samba AD in Interactive Mode
To provision a Samba AD interactively, run:
# samba-tool domain provision --use-rfc2307 --interactive Realm [SAMDOM.EXAMPLE.COM]: SAMDOM.EXAMPLE.COM Domain [SAMDOM]: SAMDOM Server Role (dc, member, standalone) [dc]: dc DNS backend (SAMBA_INTERNAL, BIND9_FLATFILE, BIND9_DLZ, NONE) [SAMBA_INTERNAL]: SAMBA_INTERNAL DNS forwarder IP address (write 'none' to disable forwarding) [10.99.0.1]: 8.8.8.8 Administrator password: Passw0rd Retype password: Passw0rd 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=samdom,DC=example,DC=com 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=samdom,DC=example,DC=com 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 4 has been generated at /usr/local/samba/private/krb5.conf Setting up fake yp server settings Once the above files are installed, your Samba4 server will be ready to use Server Role: active directory domain controller Hostname: DC1 NetBIOS Domain: SAMDOM DNS Domain: samdom.example.com DOMAIN SID: S-1-5-21-2614513918-2685075268-614796884
![]() | The interactive provisioning mode supports passing further parameters to the samba-tool domain provision command. This enables you to modify parameters that are not part of the interactive setup. |
Provisioning Samba AD in Non-interactive Mode
For example, to provision a Samba AD non-interactively with the following settings:
- Server role:
dc
- NIS extensions enabled
- Internal DNS back end
- Kerberos realm and AD DNS zone:
samdom.example.com
- NetBIOS domain name:
SAMDOM
- Domain administrator password:
Passw0rd
# samba-tool domain provision --server-role=dc --use-rfc2307 --dns-backend=SAMBA_INTERNAL --realm=SAMDOM.EXAMPLE.COM --domain=SAMDOM --adminpass=Passw0rd
Setting up the AD DNS back end
Skip this step if you provisioned the DC using the SAMBA_INTERNAL
DNS back end.
- Set up the BIND DNS server and the
BIND9_DLZ
module. For details, see Setting up a BIND DNS Server.
- Start the BIND DNS server. For example:
# systemctl start named
- For details how to start services, see you distribution's documentation.
Configuring the DNS Resolver
Domain members in an AD use DNS to locate services, such as LDAP and Kerberos. For that, they need to use a DNS server that is able to resolve the AD DNS zone.
On your DC, set the AD DNS domain in the domain
and the IP of your DC in the nameserver
parameter of the /etc/resolv.conf
file. For example:
search samdom.example.com nameserver 10.99.0.1
Create a reverse zone
You can optionally add a reverse lookup zone.
# samba-tool dns zonecreate <Your-AD-DNS-Server-IP-or-hostname> 0.99.10.in-addr.arpa Password for [administrator@SAMDOM.EXAMPLE.COM]: Zone 0.99.10.in-addr.arpa created successfully
If you need more than one reverse zone (multiple subnets), just run the above command again but with the data for the other subnet.
The reverse zone is directly live without restarting Samba or BIND.
Configuring Kerberos
In an AD, Kerberos is used to authenticate users, machines, and services.
During the provisioning, Samba created a Kerberos configuration file for your DC. Copy this file to your operating system's Kerberos configuration. For example:
# cp /usr/local/samba/private/krb5.conf /etc/krb5.conf
![]() | Do not create a symbolic link to the the generated krb5.conf file. In Samba 4.7 and later, the /usr/local/samba/private/ directory is no longer accessible by other users than the root user. If the file is a symbolic link, other users are not able to read the file and, for example, dynamic DNS updates fail if you use the BIND_DLZ DNS back end. |
The pre-created Kerberos configuration uses DNS service (SRV) resource records to locate the KDC.
Testing your Samba AD DC
To start the samba
service manually, enter:
# samba
Samba does not provide System V init scripts, systemd
, upstart
, or other services configuration files.
- If you installed Samba using packages, use the script or service configuration file included in the package to start Samba.
- If you built Samba, see Managing the Samba AD DC Service.
Verifying the File Server
To list all shares provided by the DC:
$ smbclient -L localhost -U% Domain=[SAMDOM] OS=[Unix] Server=[Samba x.y.z] Sharename Type Comment --------- ---- ------- netlogon Disk sysvol Disk IPC$ IPC IPC Service (Samba x.y.z) Domain=[SAMDOM] OS=[Unix] Server=[Samba x.y.z] Server Comment --------- ------- Workgroup Master --------- -------
![]() | The netlogon and sysvol shares were auto-created during the provisioning and must exist on a DC. |
To verify authentication, connect to the netlogon
share using the domain administrator account:
$ smbclient //localhost/netlogon -UAdministrator -c 'ls' Enter Administrator's password: Domain=[SAMDOM] OS=[Unix] Server=[Samba x.y.z] . D 0 Tue Nov 1 08:40:00 2016 .. D 0 Tue Nov 1 08:40:00 2016 49386 blocks of size 524288. 42093 blocks available
If one or more tests fail, see Troubleshooting.
Verifying DNS
To verify that your AD DNS configuration works correctly, query some DNS records:
- The tcp-based
_ldap
SRV record in the domain:
$ host -t SRV _ldap._tcp.samdom.example.com. _ldap._tcp.samdom.example.com has SRV record 0 100 389 dc1.samdom.example.com.
- The udp-based
_kerberos
SRV resource record in the domain:
$ host -t SRV _kerberos._udp.samdom.example.com. _kerberos._udp.samdom.example.com has SRV record 0 100 88 dc1.samdom.example.com.
- The A record of the domain controller:
$ host -t A dc1.samdom.example.com. dc1.samdom.example.com has address 10.99.0.1
If one or more tests fail, see Troubleshooting.
Verifying Kerberos
- Request a Kerberos ticket for the domain administrator account:
$ kinit administrator Password for administrator@SAMDOM.EXAMPLE.COM:
The Kerberos realm is automatically appended, if you do not pass the principal in the user@REALM
format to thekinit
command.
Set Kerberos realms always in uppercase.
- List the cached Kerberos tickets:
$ klist Ticket cache: FILE:/tmp/krb5cc_0 Default principal: administrator@SAMDOM.EXAMPLE.COM Valid starting Expires Service principal 01.11.2016 08:45:00 12.11.2016 18:45:00 krbtgt/SAMDOM.EXAMPLE.COM@SAMDOM.EXAMPLE.COM renew until 02.11.2016 08:44:59
If one or more tests fail, see Troubleshooting.
Configuring Time Synchronisation
Kerberos requires a synchronised time on all domain members. For further details and how to set up the ntpd
service, see Time Synchronisation.
Using the Domain Controller as a File Server
Whilst the Samba AD DC is able to provide file shares, just like all other installation modes, the Samba team does not recommend using a DC as a file server for the following reasons:
- For anything but the smallest organisations, having more than one DC is a really good backup measure, and makes upgrades safer
- It encourages upgrades of the DC to also be upgrades of the host OS every year or two, because there isn't complex data to transition or other services involved.
- This means upgrades can be done by installing fresh, and replicating in the changes, which is better tested in Samba, gains new features and avoids a number of lingering data corruption risks.
- The DC and file-server have different points at which an organisation would wish to upgrade. The needs for new features on the DC and file server come at different times. Currently the AD DC is evolving rapidly to gain features, whereas the fileserver, after over 20 years, is quite rightly more conservative.
- mandatory smb signing is enforced on the DC.
If you do decide to use the Samba DC as a fileserver, please consider running a VM, on the DC, containing a separate Samba Unix domain member and use this instead.
If you must use the Samba DC as a fileserver, you should be aware that the auto-enabled acl_xattr
virtual file system (VFS) object enables you to only configure shares with Windows access control lists (ACL). Running shares with POSIX ACLs on a Samba DC is not supported and will not work.
To provide network shares with the full capabilities of Samba, set up a Samba domain member with file shares. For details, see:
If you only have a small domain (small office, home network) and do not want to follow the Samba team's recommendation and use the DC additionally as a file server, configure Winbindd before you start setting up shares. For details, see Configuring Winbindd on a Samba AD DC.
Troubleshooting
For further details, see Samba AD DC Troubleshooting.
See User Documentation.