topic Re: publishing routes to On-Prem via Express Route in Cloud Firewall

publishing routes to On-Prem via Express Route

Nir_Shamir — Sun, 26 May 2019 09:15:28 GMT

Hi,

I have a customer who is building a Hub-And-Spoke infrastructure in Azure.

We added a Cluster-HA in his HUB vNet in order to route all the traffic from spokes vNets via the Custer to On-Prem and vice versa.

The customer has an Express Route in the HUB spoke to access the On-Prem networks. The Azure Virtual GW publish to On-Prem the networks of the HUB vNet.

This is more an Azure questions , How can I make the Express Route Virtual GW to publish the spokes vNets to On-Prem ?

I added a UDR on the GatewaySubnet to route traffic to the spokes via the CG Cluster but that route doesn't propagate to On-Prem.

Someone told me that the Express Route Virtual GW should also see the Peered vNets subnets and publish them but we don't see it.

If anyone did something similar in other customers , please advise,

Regards,

Nir

Re: publishing routes to On-Prem via Express Route

Matthias_Haas — Fri, 07 Jun 2019 09:22:52 GMT

Hi Nir,

i am not sure if it is sufficient, but have you configured the peerings as follows:

•Configure the VNet peering connection in the hub to allow gateway transit.
•Configure the VNet peering connection in each spoke to use remote gateways.
•Configure all VNet peering connections to allow forwarded traffic.

https://docs.microsoft.com/en-us/azure/architecture/reference-architectures/hybrid-networking/hub-spoke

Matthias

Re: publishing routes to On-Prem via Express Route

Martin_Valenta — Fri, 07 Jun 2019 13:12:29 GMT

Do you have BGP route propagation enabled? What do you see in effective routes?