Unable to connect from VM in peered VNETs from 1 region to another

Question

Unable to connect from VM in peered VNETs from 1 region to another

Kyle Brooks 20

I am trying to connect from a VM in centralus to eastus2 through a peered VNET between these VNETs:

/subscriptions/bc80a70f-973c-4ce3-a76f-c9b1c7316fdf/resourceGroups/rg-hub-centralus/providers/Microsoft.Network/virtualNetworks/vnet-hub-centralus

/subscriptions/bc80a70f-973c-4ce3-a76f-c9b1c7316fdf/resourceGroups/rg-hub-eastus2/providers/Microsoft.Network/virtualNetworks/vnet-hub-eastus2

I am able to connect from eastus2 to centralus but not from centralus to eastus2. They have similar routes and NSGs configured using terraform but for some reason 1 way works but not the other way.

When I run the Connection troubleshoot in network watcher it says in inbound NSG inbound rules are denying the request but they have the same NSG rules assigned for each region.

rvinnakota 4,835 Reputation points Moderator

2025-04-09T23:26:16.6666667+00:00

Hi @Kyle Brooks

Just checking in to see if the below answer provided by Abiola Akinbade helped.

If this answers your query, do click Accept Answer and Yes for was this answer helpful. And, if you have any further query do let us know.
rvinnakota 4,835 Reputation points Moderator

2025-04-10T07:36:56.97+00:00

Hi @Kyle Brooks,

Glad to know that your issue has been resolved. And thanks for sharing the solution, 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.
rvinnakota 4,835 Reputation points Moderator

2025-04-10T10:54:38.0866667+00:00

Hi @Kyle Brooks,
I'm glad that you were able to resolve your issue and thank you for posting your solution so that others experiencing the same thing can easily reference this!

Since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others", I'll repost your solution.

Please click "Accept" the answer as original posters help the community find answers faster by identifying the correct answer.

Issue: Unable to connect from VM in peered VNETs from 1 region to another

Resolution: I ended up deleting everything and recreating it using Terraform and the issue was gone.

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.

Answer accepted by question author

0 additional answers

Your answer

rvinnakota 4,835 Reputation points Moderator

2025-04-09T23:26:16.6666667+00:00

Hi @Kyle Brooks

Just checking in to see if the below answer provided by Abiola Akinbade helped.

If this answers your query, do click Accept Answer and Yes for was this answer helpful. And, if you have any further query do let us know.
rvinnakota 4,835 Reputation points Moderator

2025-04-10T07:36:56.97+00:00

Hi @Kyle Brooks,

Glad to know that your issue has been resolved. And thanks for sharing the solution, 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.
rvinnakota 4,835 Reputation points Moderator

2025-04-10T10:54:38.0866667+00:00

Hi @Kyle Brooks,
I'm glad that you were able to resolve your issue and thank you for posting your solution so that others experiencing the same thing can easily reference this!

Since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others", I'll repost your solution.

Please click "Accept" the answer as original posters help the community find answers faster by identifying the correct answer.

Issue: Unable to connect from VM in peered VNETs from 1 region to another

Resolution: I ended up deleting everything and recreating it using Terraform and the issue was gone.

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.

Answer 1

Abiola Akinbade 30,500 Volunteer Moderator

It sounds like you're experiencing a one-way connectivity issue with your peered VNETs. You will need to check that both VNETs have peering configured properly with the correct settings:

Check that Allow virtual network access is enabled on both sides
In Azure Portal: VM > Networking > Network Interface > Effective Security Rules
Confirm "Allow forwarded traffic" is enabled if needed
You can also check the Terraform state or plan outputs for both NSGs to identify any subtle differences
Check for default deny rules that might be affecting traffic

See: https://learn.microsoft.com/en-us/azure/virtual-network/network-security-group-how-it-works

You can mark it 'Accept Answer' and 'Upvote' if this helped you

Regards,

Abiola

Kyle Brooks 20 Reputation points

2025-04-09T23:40:49.8633333+00:00

I ended up deleting everything and recreating it using Terraform and the issue was gone. I'm not sure what caused it. I would accept the answer but I don't see that button / option.