> ## 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.
# Transit Gateway Integration with AWS VGW Workflow
> Aviatrix automates the process of discovering and connecting Aviatrix Transit Gateway to AWS VGW.
Aviatrix automates the process of discovering and connecting Aviatrix Transit
Gateway to AWS VGW.
Before connecting an Aviatrix Transit Gateway to AWS VGW, a VGW must have
already been created on the AWS console. In the AWS console, note the VGW ID
that is created for the VGW.
When you setup the connection by providing the VGW ID, a Customer Gateway and a
Site2Cloud connection between the VGW and the Aviatrix Transit Gateway will be
automatically created. The Site2Cloud IPsec tunnel establishes a BGP session to
exchange routes between on-premises and the cloud.
After successful creation of the connection, you can view connection in the AWS
console by navigating to Customer Gateways and Site-to-Site VPN Connections.
You are responsible for building the connection between VGW and on-premises.
The connection is either over the Internet, over Direct Connect, or both.
Aviatrix supports two types of connections: Detached VGW and Attached VGW.
The VGW should not be attached to the Transit VPC or VNet.
The VGW can be attached to a VPC or VNet in a different AWS account in a
different region.
## Connecting Transit Gateway to AWS VGW
This document describes the workflow to connect an Aviatrix Transit Gateway to
an AWS Virtual Private Gateway (VGW).
The procedure below assumes the AWS VGW is already deployed in the Transit VPC.
To connect the Transit Gateway to AWS VGW (VPN Gateway):
1. In Aviatrix CoPilot, go to **Networking > Connectivity > External Connections
(S2C)** tab.
2. From the **+ External Connection** dropdown menu, select **AWS Virtual
Gateway**.
3. Enter the following values:
| Field | Description |
| -------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Name | A name to identify the connection to the VGW. |
| Local Gateway | The Transit Gateway to connect to the VGW. |
| Local ASN | The BGP AS Number the Transit Gateway will use to exchange routes with the VGW. |
| VGW Account Name | The name of the AWS access account with which the VGW was created. |
| VGW Region | The AWS region where the VGW is located. |
| VGW ID | The unique identifier for the VGW. |
| Manual CIDR Approval | This is Off and disabled by default unless the Local Gateway you select has **[Manual Learned CIDR Approval](https://legacy.docs.aviatrix.com/documentation/latest/network/bgp-connection-settings.html#gateway-learned-cidr-approval)** turned On for Connection Level. Then it is On by default (not editable). |
4. Click **Save**.
The new AWS VGW connection appears in the table.
It takes a few minutes for the VPN connection to come up and routes from VGW to
be propagated. When the IPsec tunnel with a VGW is up, the Controller admin
should receive an email notification.
If you log in to the AWS Console and select *service VPC* in the region where
the VGW is, you should see that the Customer Gateway and VPN Connections have
been created. Do not delete or modify them from AWS Console. These resources are
deleted if you disconnect the VGW.
## Checking Route Propagation
You can check if routes are properly propagated.
1. Go to **Diagnostics > Cloud Routes > BGP Info**.
2. In the table, next to the name of the Transit Gateway used in the above
external connection.
3. Click the vertical ellipsis
and select
**Show BGP Learned Routes** to display the total number and list of routes
propagated from the VGW.
## Checking Tunnel Status
You can check the tunnel connection between the AWS VGW and the Transit Gateway
from **Diagnostics > Cloud Routes > BGP Info**. Expand the Transit Gateway in
the list and check that the Status column shows Established.
If some external connections for the selected Transit Gateway are Not
Established, the overall BGP Status for the Transit Gateway is Partially
Established.
## Related Topics
* [Viewing External Connection Details](https://legacy.docs.aviatrix.com/documentation/latest/network/external-connection-details.html?expand=true)
* [Disconnecting an External Connection](https://legacy.docs.aviatrix.com/documentation/latest/network/external-connection-disconnect.html)