> ## Documentation Index
> Fetch the complete documentation index at: https://docs.aviatrix.com/llms.txt
> Use this file to discover all available pages before exploring further.

# DNS Server Configuration for Aviatrix Services

> This document provides an overview of how DNS (Domain Name System) servers are configured within Aviatrix services. DNS is a critical infrastructure component that translates domain names into IP addresses, enabling communication between Aviatrix components and external systems.

This document provides an overview of how DNS (Domain Name System) servers are
configured within Aviatrix services. DNS is a critical infrastructure component
that translates domain names into IP addresses, enabling communication between
Aviatrix components and external systems.

Proper DNS configuration ensures reliable name resolution, system reachability,
and integration with cloud and on-premises services.

## Supported DNS Options

Aviatrix supports the following types of DNS configurations:

* **Aviatrix Default DNS Server**: This option is suitable for most
  internet-based resolution needs.
* **Cloud VPC/VNet DNS Server**: The Cloud VPC/VNet DNS server is automatically
  assigned through the VPC or VNet DHCP option sets and is used to resolve
  internal services within the same cloud network.
* **Custom DNS Servers**: This option uses user-defined IPv4 addresses,
  typically used for resolving internal domains or applying network-specific DNS
  policies.

## Components That Require DNS

The following Aviatrix components rely on DNS servers for their core operations:

### Aviatrix Controller

The Aviatrix Controller requires DNS for licensing, CoPilot integration,
telemetry reporting, and external API access.

* Default Setting
  * The Aviatrix Default DNS server uses Google Public DNS servers.

* Optional Setting
  * **Cloud VPC/VNet DNS Server**: This option uses DNS servers configured
    through the VPC/VNet DHCP option set.

See

<a href={"/docs/enterprise/" + "10.1" + "/guides/platform-administration/copilot-dns-controller"}>DNS Server Configurations for the Aviatrix Controller</a>
for more information.

### Aviatrix CoPilot

The Aviatrix CoPilot depends on DNS to reach API endpoints, support integration
services, and perform connectivity checks to cloud resources.

* Default Setting
  * **Cloud VPC/VNet DNS Server**: This option uses cloud-assigned DNS for
    consistent resolution within the environment.

* Optional Setting
  * **Custom DNS Servers**: This option allows configuration of up to two custom
    DNS IPv4 addresses for resolving internal or private domains.

See

<a href={"/docs/enterprise/" + "10.1" + "/reference/ui/settings/configuration#configure-advanced-settings"}>DNS Server Configuration for the Aviatrix CoPilot</a>
for more information.

### Aviatrix Gateways

Gateways use DNS servers to resolve hostnames used in SmartGroups, logging,
egress policies, and communication with cloud services.

* Default Setting
  * The Aviatrix Default DNS server uses Google Public DNS servers.

* Optional Setting
  * **Cloud VPC/VNet DNS Server**: The Cloud VPC/VNet DNS Server is
    automatically configured via cloud DHCP.

See

<a href={"/docs/enterprise/" + "10.1" + "/reference/gateways/transit-spoke-dns"}>DNS Server Configuration for Aviatrix Gateways</a>
for more information.

### Hostname Resource-Type SmartGroups

For SmartGroups where the resource type is set to `Hostname`, DNS is required to
evaluate and resolve hostnames used in security and routing policies.

* Default Setting
  * **Gateway's Management DNS Server**: Each gateway uses its own individually
    configured DNS setting.

* Optional Setting
  * **Custom DNS Servers**: This option supports up to two DNS IPv4 addresses.
    These settings are applied to all gateways that enforce the SmartGroup.

See

<a href={"/docs/enterprise/" + "10.1" + "/concepts-architectures/components/dcf/hostname-smartgroups-about#dns-server-configuration"}>DNS Server for Hostname Resolution (Hostname SmartGroups)</a>
for more information.

## DNS Setting Summary

| Component                          | Default Setting               | Option Settings                        |
| ---------------------------------- | ----------------------------- | -------------------------------------- |
| Controller                         | Aviatrix Default DNS          | Cloud VPC/VNet DNS                     |
| CoPilot                            | Cloud VPC/VNet DNS            | Custom DNS Servers                     |
| Gateways                           | Aviatrix Default DNS          | Cloud VPC/VNet DNS, Custom DNS Servers |
| Hostname Resource-Type SmartGroups | Gateway Management DNS Server | Custom DNS Servers                     |