# Add a BGP peer to an Direct Connect virtual interface
<a name="add-peer-to-vif"></a>

Add or delete an IPv4 or IPv6 BGP peering session to your virtual interface using either the Direct Connect console or using the command line or API.

A virtual interface can support a single IPv4 BGP peering session and a single IPv6 BGP peering session. You cannot specify your own peer IPv6 addresses for an IPv6 BGP peering session. Amazon automatically allocates you a /125 IPv6 CIDR. 

Multi-protocol BGP is not supported. IPv4 and IPv6 operate in dual-stack mode for the virtual interface.

AWS enables MD5 by default. You cannot modify this option.

Use the following procedure to add a BGP peer.

**To add a BGP peer**

1. Open the **Direct Connect** console at [https://console.aws.amazon.com/directconnect/v2/home](https://console.aws.amazon.com/directconnect/v2/home).

1. In the navigation pane, choose **Virtual Interfaces**.

1. Select the virtual interface and then choose **View details**.

1. Choose **Add peering**.

1. (Private virtual interface) To add IPv4 BGP peers, do the following:
   + Choose **IPv4**.
   + To specify these IP addresses yourself, for **Your router peer ip**, enter the destination IPv4 CIDR address to which Amazon should send traffic. For **Amazon router peer ip**, enter the IPv4 CIDR address to use to send traffic to AWS.

1. (Public virtual interface) To add IPv4 BGP peers, do the following:
   + For **Your router peer ip**, enter the IPv4 CIDR destination address where traffic should be sent.
   + For **Amazon router peer IP**, enter the IPv4 CIDR address to use to send traffic to AWS.
**Important**  
When configuring AWS Direct Connect virtual interfaces, you can specify your own IP addresses using RFC 1918, use other addressing schemes, or opt for AWS assigned IPv4 /29 CIDR addresses allocated from the RFC 3927 169.254.0.0/16 IPv4 Link-Local range for point-to-point connectivity. These point-to-point connections should be used exclusively for eBGP peering between your customer gateway router and the Direct Connect endpoint. For VPC traffic or tunnelling purposes, such as AWS Site-to-Site Private IP VPN, or Transit Gateway Connect, AWS recommends using a loopback or LAN interface on your customer gateway router as the source or destination address instead of the point-to-point connections.   
For more information about RFC 1918, see [Address Allocation for Private Internets](https://datatracker.ietf.org/doc/html/rfc1918).
For more information about RFC 3927, see [Dynamic Configuration of IPv4 Link-Local Addresses](https://datatracker.ietf.org/doc/html/rfc3927).

1. (Private or public virtual interface) To add IPv6 BGP peers, choose **IPv6**. The peer IPv6 addresses are automatically assigned from Amazon's pool of IPv6 addresses; you cannot specify custom IPv6 addresses.

1. For **BGP ASN**, enter the Border Gateway Protocol Autonomous System Number of your on-premises peer router for the new virtual interface.

   For a public virtual interface, the ASN must be private or already on the allow list for the virtual interface.

   The valid values are 1 to 4294967294. This includes support for both ASNs (1-2147483646) and long ASNs (1-4294967294). For more information about ASNs and long ASNs see [Long ASN support in Direct Connect](long-asn-support.md).

   Note that if you do not enter a value, we automatically assign one.

1. To provide your own BGP key, for **BGP Authentication Key**, enter your BGP MD5 key.

1. Choose **Add peering**.

**To create a BGP peer using the command line or API**
+ [create-bgp-peer](https://docs.aws.amazon.com/cli/latest/reference/directconnect/create-bgp-peer.html) (AWS CLI)
+ [CreateBGPPeer](https://docs.aws.amazon.com/directconnect/latest/APIReference/API_CreateBGPPeer.html) (Direct Connect API)