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

# Configuring a NAT Gateway VXC

> This help topic describes how to configure a VXC connected to a NAT Gateway, including interfaces, IP addresses, BGP connections, and static routes.

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For each VXC connected to a Megaport NAT Gateway (NAT Gateway), you can configure one or more interfaces, IP addresses, BGP connections, or static routes. You can also select a NAT source IPv4 address and specify the IP MTU value.

For information about creating a new connection from a Megaport NAT Gateway, see [Creating a NAT Gateway VXC](/nat/nat-gateway-vxc).

Depending on the VXC destination or cloud service provider, the NAT Gateway connection settings might have been auto-configured during VXC creation. Follow the steps in this task to configure the connection settings as required.

<Note>
  If the VXC provisioning status is LIVE, CONFIGURED, or DEPLOYABLE, the connection configuration fields are available when editing a VXC, regardless of provider.
</Note>

**To edit a VXC interface**

1. Select the NAT Gateway VXC you want to edit.

2. Select the VXC A-End or B-End.

   <Image src="/images/nat/nat-vxc-a-end-settings.png" shadow={true} width={800} />

3. Enter a description for the connection.

4. Enter one or more interface IP addresses and subnet masks to configure on the A-End interface.

5. (Optional) Enter an <Gloss term="IP MTU (Maximum Transmission Unit)" anchor="ipmtu" /> value (in bytes) for the VXC.\
   The IP MTU can range from 1280 to 9070 (9074 if Q-in-Q is disabled). The default value is 1500.

6. Enter any details specific to the VXC type.
   * For more information about using NAT Gateway Pools, see [Using NAT Gateway Pools](/nat/nat-gateway-pools).
   * For more information about using packet filters, see [Using Packet Filters](/nat/packet-filters).
   * For more information about adding a BGP connection, see [Configuring BGP for Megaport NAT Gateway](/nat/configure-bgp).
   * For more information about enabling Bidirectional Forwarding Detection (BFD) settings, see [Enabling the BFD protocol](/nat/bgp-advanced#bfd-protocol).
   * For more information about adding a static route, see [Configuring Static Routing on a Megaport NAT Gateway](/nat/static-routing).

7. Click **Save**.

## Helpful references

* [Configuring Advanced BGP Settings](/nat/bgp-advanced)
* [Configuring BGP for Megaport NAT Gateway](/nat/configure-bgp)
* [Configuring Static Routing on a Megaport NAT Gateway](/nat/static-routing)
* [Creating a NAT Gateway VXC](/nat/nat-gateway-vxc)
* [NAT Gateway Features](/nat/nat-gateway-features)