Routing between two subnets

Question

Hi, I've created two subnets on the same virtual network.
I've defined a default route to a Azure firewall in this vnet.
I can reach two sample hosts (one on each subnet) with RDP from internet, passing through the firewall.
But If I try to produce traffic from a host to the other and vice versa, this traffic doesn't go to firewall.
How to solve?

Answer 1

"Hub&Spoke" is the name of a network topology, nothing "Azure-Special":

Hub-spoke network topology in Azure

Regards

Andreas Baumgarten

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Answer 2

In the same vNET it's routed by default, but if you have two vNET's you have to configure Route table

also check this article
https://learn.microsoft.com/en-us/azure/architecture/reference-architectures/hybrid-networking/hub-spoke#deploy-the-solution

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Answer 3

Maybe this is helpful:

Virtual network traffic routing

Though a virtual network contains subnets, and each subnet has a defined address range, Azure does not create default routes for subnet address ranges, because each subnet address range is within an address range of the address space of a virtual network.

Regards

Andreas Baumgarten

(Please don't forget to Accept as answer if the reply is helpful)

Answer 4

Hi, thank your for reply but how can I "separate" the two subnets?
I need that from a subnet I can reach the other and NOT vice versa...

Answer 5

As two subnets in one virtual network are "routed by default" the only way I can think of is creating 2 virtual networks with one subnet in each virtual network.
This way you should be able to work with routes.

If you just want to block communication maybe a Network Security Group (NSG) is an option as well. But this is not routing based control of communication but is more simple allow/deny ruleset for communication.

Regards

Andreas Baumgarten

(Please don't forget to Accept as answer if the reply is helpful)