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.. |date| date::

.. meta::
  :description: About DNS
  :keywords: DNS, Samba, documentation

.. _about_dns:

#########
About DNS
#########

The :abbr:`DNS (Domain Name Service)` service manages the resolution of Active Directory internal names.
It replaces the NetBios resolution in NT domains.

.. table:: Ports used by the DNS service

  ==== ==========
  Port Usage
  ==== ==========
  53   TCP and UDP
  ==== ==========

Two options are available:

* Since Samba 4.17, it is **recommended to use the hybrid DNS mode with Bind9 for optimal performance and scalability**. However, Samba-AD still includes its own internal DNS server, which is fully operational upon installation.

* For a more advanced or intense use of DNS, the Samba-team advises to use Bind9 as DNS backend (9.8 minimum version).

You may find useful to follow the Bind documentation for :ref:`Debian and derivatives <server_install_hybrid_dns_debian>` or :ref:`Redhat and derivatives <server_install_hybrid_dns_redhat>`.