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Hi All,
I recently created a VPN gateway under my vnet which has an address space or 11.1.0.0/16. However I am using Site to Site VPN setting to connect to my OnPrem resources which has the following address space.
10.0.0.0/24
177.16.120.0/21
192.168.3.0/24
Now my issue is that I can connect to my OnPrem machines which falls in the 177 and 192 series but I CANT CONNECT to any resource in my onprem environment which falls in the 10.0.0.XX series like 10.0.0.26
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@Red Matter Architect Thank you for reaching out to Microsoft Q&A. Firstly apologize for the delay in response to your question.
I understand that you are facing connectivity issues to one of the address ranges on your on-premise i.e., 10.0.0.0/24. Can you share more details/snapshots of your route table on the Azure side subnet? Can you also confirm if there are any security rules on the on-premise blocking access to this 10/24 network? Are there any conflicting routes on Azure with the same/similar subnet? Please let us know. Thank you!
Hello Sai,
Thanks for replying. We have not created any route tables explicitly for the on-prem connectivity. Also there is no IP range that conflicts with the 10.0.0.0/24 subnet series. I am checking with my IT Manager for any inbound rules but just to let you know that none of my onPrem machines are able to connect to Azure as well. So the VPN tunnel (Site to Site connectivity is up and running) is only not able to talk for this specific series. Hence are there any internal Azure restrictions for this particular subnet series.
@Red Matter Architect There are no restrictions for this specific subnet on Azure cloud as such. I understand that you did not create a route table explicitly but can you share a snapshot or copy/paste the routes in the subnets route table so I can take a look?
@Red Matter Architect This is a snapshot of the subnet itself. Its useful to see the actual routes associated to the subnet. Can you provide those?
Can you please help as where can i find by giving me the direction so that i can share the right information with you because when i search for route tables, nothing shows up as i have not configured any routes
@Red Matter Architect Please check the steps given here in the document to find the effective routes for the NIC of the VM from which you are testing connectivity from. Please share the snapshot of the effective route table. Thank you!
@Red Matter Architect Routing looks good i.e., I can see a route for the 10.0.0.0/24 network and this route will be used for 10/24 network as the longest prefix matches to this one. Have you performed any traffic captures on the on-premise side to see if the traffic reaches the on-premise side? If not, I will start there and check if traffic is reaching or not.
@Red Matter Architect Any update?
Nothing so far because we are working on an alternate solution for this.
Thanks for the support.
You can close the thread
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