ER Direct with FastPath on GW connection and UDRs in GW subnet

Thomas Hornbæk Winther 0 Reputation points
2024-11-12T07:56:16.13+00:00

In a non-VWAN hub'n'spoke setup, can I be sure that my GW Subnet UDRs are honored, even with FastPath enabled on the ER GW connection to my ER Direct Circuit?

Can I verify it in CLI somehow?

Thanks!

/Thomas Winther

Azure Virtual WAN
Azure Virtual WAN
An Azure virtual networking service that provides optimized and automated branch-to-branch connectivity.
231 questions
Azure Virtual Network
Azure Virtual Network
An Azure networking service that is used to provision private networks and optionally to connect to on-premises datacenters.
2,551 questions
Azure ExpressRoute
Azure ExpressRoute
An Azure service that provides private connections between Azure datacenters and infrastructure, either on premises or in a colocation environment.
391 questions
{count} votes

1 answer

Sort by: Most helpful
  1. Ganesh Patapati 2,275 Reputation points Microsoft Vendor
    2024-11-15T07:02:13.2133333+00:00

    Hi Thomas Hornbæk Winther,

    We appreciate your Patience!

    Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.

    Please find the confirmation from the Azure ExpressRoute product team below:

    Question: In a non-VWAN hub'n'spoke setup, can I be sure that my GW Subnet UDRs are honored, even with FastPath enabled on the ER GW connection to my ER Direct Circuit?

    • Yes, your UDRs on the GW subnet with FP enabled are honored.

    Refer: https://learn.microsoft.com/en-us/azure/expressroute/about-fastpath#circuits

    https://techcommunity.microsoft.com/blog/azurenetworkingblog/expressroute-fastpath-for-udrs-and-vnet-peering/4171115

    Question: Can I verify it in CLI somehow?

    Yes, you can validate FastPath & UDRs via the route table with Azure PowerShell:

    • FastPath:
    Get-AzVirtualNetworkGateway -Name <GatewayName> -ResourceGroupName <ResourceGroupName> | Select-Object -ExpandProperty EnableFastPath - Command 
    

    will return True if FP is enabled. False if it's not.

    • UDR: Retrieve the route table with
    $routeTable = Get-AzRouteTable -Name <RouteTableName> -ResourceGroupName <ResourceGroupName>
    

    list the routes & check to ensure your UDR is honored/present: $routeTable.Routes


    Hope this clarifies,

    Please don’t forget to close the thread by clicking "Accept the answer" wherever the information provided helps you, as this can be beneficial to other community members.

    Regards,

    Ganesh

    0 comments No comments

Your answer

Answers can be marked as Accepted Answers by the question author, which helps users to know the answer solved the author's problem.