Attaching a VPC to the Transit Gateway
You can attach an existing VPC to the FortiGate Autoscale with Transit Gateway environment by manually creating a Transit Gateway attachment and adding the necessary routes, propagations, and associations:
- Create a Transit Gateway attachment.
- Create a route to the Transit Gateway.
- Create a propagation in the inbound route table.
- Create an association in the outbound route table.
|
The CIDR block for the VPC you are attaching must differ from that of the FortiGate Autoscale VPC. |
In the instructions that follow, the VPC transit-gateway-demo-vpc01 with CIDR 10.0.0.0/16 will be attached to the FortiGate Autoscale with Transit Gateway environment.
To create a Transit Gateway attachment:
- In the left navigation tree, click TRANSIT GATEWAYS > Transit Gateway Attachment.
- Click Create Transit Gateway Attachment.
- Specify information as follows:
- Transit Gateway ID: Select from the dropdown menu
- Attachment type: VPC
- Attachment name tag: Enter a tag of your choice
- VPC ID: Select from the dropdown menu
- Subnet IDs: This option appears once the VPC ID has been selected. Check the Availability Zone check box(es) and choose 1 subnet per Availability Zone.
- Click Create attachment.
- Wait for the State to change from pending to available.
The Name is what you specified for the Attachment name tag.
- When the State is available, click on the Resource ID to go to the VPC.
To create a route to the Transit Gateway:
- In the VPC, click on the Route table.
- Click the Routes tab and then click Edit routes.
- Click Add route and specify the Destination, for example, 10.1.0.0/16. Under Target, select Transit Gateway.
- Then dropdown will change to display available Transit Gateways. Select the one created by the deployment stack and then click Save routes.
|
|
If you want to route all traffic to the Transit Gateway, you should add a new route for destination 0.0.0.0/0. If this route already exists, simply remove the route and add a new one for the same destination with the target set to the Transit Gateway created by the deployment stack. |
To create a propagation in the inbound route table:
- In the left navigation tree, click Transit Gateways > Transit Gateway Route Tables.
- Select the <ResourceTagPrefix>-transit-gateway-route-table-inbound route table.
- Click the Propagations tab and then click Create propagation.
- From Choose attachment to propagate, select the attachment created in the section To create a Transit Gateway attachment:.
- Click Create propagation and then click Close.
- The new propagation with Resource type VPC is now listed on the Propagations tab.
- Click on the Routes tab to see that the route for your VPC has been automatically propagated.
To create an association in the outbound route table:
- In the left navigation tree, click Transit Gateways > Transit Gateway Route Tables.
- Select the <ResourceTagPrefix>-transit-gateway-route-table-outbound route table.
- Click the Associations tab and then click Create association.
- From Choose attachment to associate, select the attachment created in the section To create a Transit Gateway attachment:.
- Click Create association and then click Close.
- The new association with Resource type VPC is now listed on the Associations tab.
The VPC is now connected to the FortiGate Autoscale Transit Gateway. For a technical view of attaching VPCs to the FortiGate Autoscale Transit Gateway, please refer to the architectural diagram .