Connecting Two Aviatrix Transit Clusters

This tech note demonstrates how to connect two Aviatrix Transit Network clusters by using an additional Aviatrix gateway in one Transit Network cluster and creating a site2cloud connection between that Aviatrix gateway and the VGW in the other Transit Network cluster.


Environment Requirements

There are two Transit Network clusters as illustrated in the diagram below.

image1

Transit Network Cluster1 on the left side includes:

  • Two spokes VPCs: The CIDRs are tn1-spoke1-cidr(10.1.0.0/16), tn1-spoke2-cidr(10.2.0.0/16)
  • One transit VPC: The CIDR is tn1-transit-cidr(10.100.0.0/16)
  • BGP site2cloud connection between transit gateway and VGW: tn1-transit-s2c
  • On-Prem 1

Transit Network Cluster2 on the right side includes:

  • Two spokes VPCs: The CIDRs are tn2-spoke1-cidr(192.168.1.0/24), tn2-spoke2-cidr(192.168.2.0/24)
  • One Transit VPC: The CIDR is tn2-transit-cidr(192.168.100.0/24)
  • BGP site2cloud connection between transit gateway and VGW: tn2-transit-s2c
  • On-Prem 2

The following steps create a full mesh network among all spoke VPCs and the Transit VPCs as described in the above diagram.

Steps to Connect Two Aviatrix Transit Network Clusters

  • Step 1: Launch a regular Aviatrix gateway (tn1-s2c-gw) in Transit Network Cluster1’s transit VPC

Launch Aviatrix Gateway by following instructions in this document

image2

  • Step 2: Create a static site2cloud connection between tn1-s2c-gw and VGW of Transit Network Cluster2.

image3

Note

In the Aviatrix terminology, Site2Cloud is the name of the feature that enables connections from one site (or datacenter) to other sites (including cloud environments).

Please follow instructions in this document to create the site2cloud connection.

The Remote Subnet(s) should include all the VPC CIDRs of Transit Network Cluster2(tn2-spoke1-cidr, tn2-spoke2-cidr and tn2-transit-cidr). The Local Subnet(s) should include all the VPC CIDRs of Transit Network Cluster1(tn1-spoke1-cidr, tn1-spoke2-cidr and tn1-transit-cidr).

Field Value
Remote Subnet(s) 192.168.1.0/24,192.168.2.0/24,192.168.100.0/24
Local Subnets(s) 10.1.0.0/16,10.2.0.0/16,10.100.0.0/16
  • Step 3: Edit AWS VGW to tn1-s2c-gw VPN connection in Transit Network Cluster2

From AWS console, add static routes for all the CIDRs in Transit Network Cluster1.

image4

  • Step 4: Enable “Advertise Transit VPC Network CIDR(s)” for both transit network BGP site2cloud connections:tn1-transit-s2c and tn2-transit-s2c.

image5

This will allows instances in Transit VPC talk to instances in Spoke VPCs

  • Step 5: Enable “Connected Transit” for both transit network BGP site2cloud connections:tn1-transit-s2c and tn2-transit-s2c

image6

This will allows instances in Spoke VPCs can talk to each other

  • Step 6: Open up Security Group for site2cloud gateway tn1-s2c-gw in Transit Network Cluster1’s transit VPC.

From AWS console, edit SG Inbound rule: Add allow All Traffic for all Transit Network Cluster1 Spoke CIDRs: in this case, tn1-spoke1-cidr and tn1-spoke2-cidr.

image7

  • Step 7: Open up Security Group for transit gateway tn1-transit-gw in Transit Network Cluster1’s transit VPC.

From AWS console, edit SG Inbound rule: Add allow All Traffic for all Transit Network Cluster2 CIDRs: in this case, tn2-spoke1-cidr, tn2-spoke2-cidr and tn2-transit-cidr.

image8

Test Connections between Transit Network Clusters

Ping from any Ubuntu VM in any VPC of Transit Network Cluster1 to another Ubuntu VM in Transit Network Cluster2.