Your on-premises data center has 2 routers connected to your Google Cloud environment through a VPN on each router.
All applications are working correctly; however, all of the traffic is passing across a single VPN instead of being load-balanced across the 2 connections as desired.
During troubleshooting you find: " Each on-premises router is configured with a unique ASN.
" Each on-premises router is configured with the same routes and priorities.
" Both on-premises routers are configured with a VPN connected to a single Cloud Router.
" BGP sessions are established between both on-premises routers and the Cloud Router.
" Only 1 of the on-premises router's routes are being added to the routing table.
What is the most likely cause of this problem?
Click on the arrows to vote for the correct answer
A. B. C. D.D.
The most likely cause of this problem is option A - The on-premises routers are configured with the same routes.
The problem is that traffic is not being load-balanced across the 2 VPN connections, which indicates a routing problem. Given that the two routers are each configured with a unique ASN, and BGP sessions are established between both on-premises routers and the Cloud Router, it is reasonable to assume that the issue is related to routing configuration.
The fact that only one of the on-premises router's routes is being added to the routing table indicates that there is a route preference issue. When BGP establishes a connection between routers, it sends a list of routes with certain attributes, including a metric that is used to determine the best path for the traffic. If both routers are sending the same routes with the same metric, the Cloud Router will choose only one of the routes to add to its routing table, effectively ignoring the other.
To resolve the issue, the on-premises routers should be configured with different routes or different route metrics, so that the Cloud Router can load-balance traffic across both VPN connections. The ASN configuration is not likely to be the cause of the problem, as long as each router has a unique ASN. The lack of a load balancer is also not relevant to the issue, since the routing problem needs to be resolved first. Finally, a firewall blocking traffic across the second VPN connection is also not likely to be the issue, as both VPN connections are established and BGP sessions are running.