question

Hello @wisnia ,

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

In order to view topology in Network Watcher, the respective resource group should have network resources and it is only for showing Network Components. The topology capability of Azure Network Watcher enables you to view all of the resources in a virtual network, the resources associated to resources in a virtual network, and the relationships between the resources. Network Watcher Topology will only support resource group which has at least one Vnet.

Refer : https://docs.microsoft.com/en-us/azure/network-watcher/view-network-topology

I would request you to validate the resource group which you are trying to check in Network Watcher topology and confirm that it has at least 1 Vnet in it. If it doesn't have any Vnet in it, then Network watcher will not show it.

You could also try to use Azure PowerShell/CLI to view the topology.
Refer : https://docs.microsoft.com/en-us/azure/network-watcher/view-network-topology#view-topology---powershell

Topology information is only returned for resources that are within the same resource group as the only you select and the same region as the network watcher. For example, a network security group that exists in a resource group other than the one you select, isn't shown, even if the network security group is associated to a subnet in the virtual network deployed in that particular resource group.

Kindly let us know if the above helps or you need further assistance on this issue.

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