Virtual Network unable to remove/delete Connected devices

Question

Virtual Network unable to remove/delete Connected devices

Mitch Abel 5

I have added a waf_v2 application gateway which had some errors. Redeploying the App Gateway says the subnet is now in use by other resources.

Looking at connected devices there are the following which I believe are managed by Microsoft.

I am unable to delete these resources, any options to remove them?

How do we prevent this from happening again?

Screenshot 2025-04-12 151628

Obinna Ejidike 500 Reputation points

2025-04-12T06:42:53.85+00:00
Hi Mitch Abel

Thanks for using the Q&A platform

The three resources are Microsoft-managed resources created automatically when deploying an Application Gateway (WAF_v2 SKU). These resources are tied to the App Gateway's infrastructure and can't be deleted manually.

Microsoft sometimes delays cleaning up the subnet. After deleting the App Gateway, wait for a while and run the command below to check the subnet:

az network vnet subnet show --name <subnet> --vnet-name <vnet> --resource-group <rg>

If empty, you can proceed to redeploy; however, the App Gateway deletion sometimes fails silently.

Additionally, you can run the below command to forcefully delete:

az network application-gateway delete --name <your-appgw-name> --resource-group <your-rg>

Find Microsoft documentation for additional information: https://learn.microsoft.com/en-us/cli/azure/network/application-gateway?view=azure-cli-latest#az-network-application-gateway-delete-examples

If the resource persists and blocks subnet reuse, kindly raise a Microsoft support request for further assistance.

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

Regards,

Obinna
Mitch Abel 5 Reputation points

2025-04-12T11:09:34.6266667+00:00

Thanks Obinna,

The App Gateway was deleted some time ago, the resource itself might be removed and redeployed several times during development and testing.

If a support ticket with Microsoft has to be raised every single time to remove the hidden resources, that won't be ideal. Is there no way to detach these resources? Scaling the App Gateway to 0 before deleting maybe?
Sai Prasanna Sinde 5,010 Reputation points Microsoft External Staff

2025-04-14T11:15:07.96+00:00
Hi @Mitch Abel

Ideally, you can have multiple instances of a specific Application Gateway deployment in a subnet.

See: Virtual network and dedicated subnet - this means, you should be technically able to deploy a new gateway.

However, it's possible that the residual resources aren't a full pledged app gateway and could be leading to this issue.

May I ask what happens when you delete the subnet?

Can you share the exact error message/ screenshot?

Also, please leverage Azure Powershell / CLI instead of portal.

Refer: https://learn.microsoft.com/en-us/azure/virtual-network/virtual-network-manage-subnet?tabs=azure-powershell#delete-a-subnet

When you deleted the original App gateway, was there a success message or was there any errors?

You can find this information from the resource group's Activity logs

Filter for the right time stamp and you should see Delete Operation on App Gateway.

Can you confirm if the "Status" of this operation shows as "Succeeded"?

Kindly let us know if the above helps or you need further assistance on this issue.
Venkat V 1,390 Reputation points Microsoft External Staff

2025-04-16T06:05:57.78+00:00

Hi @Mitch Abel

I just wanted to follow up and see if you had a chance to review my response to your question. Please let us know if it was helpful, and feel free to reach out if you have any further queries.

1 answer

Your answer

Obinna Ejidike 500 Reputation points

2025-04-12T06:42:53.85+00:00

Hi Mitch Abel

Thanks for using the Q&A platform

The three resources are Microsoft-managed resources created automatically when deploying an Application Gateway (WAF_v2 SKU). These resources are tied to the App Gateway's infrastructure and can't be deleted manually.

Microsoft sometimes delays cleaning up the subnet. After deleting the App Gateway, wait for a while and run the command below to check the subnet:

az network vnet subnet show --name <subnet> --vnet-name <vnet> --resource-group <rg>

If empty, you can proceed to redeploy; however, the App Gateway deletion sometimes fails silently.

Additionally, you can run the below command to forcefully delete:

az network application-gateway delete --name <your-appgw-name> --resource-group <your-rg>

Find Microsoft documentation for additional information: https://learn.microsoft.com/en-us/cli/azure/network/application-gateway?view=azure-cli-latest#az-network-application-gateway-delete-examples

If the resource persists and blocks subnet reuse, kindly raise a Microsoft support request for further assistance.

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

Regards,

Obinna
Mitch Abel 5 Reputation points

2025-04-12T11:09:34.6266667+00:00

Thanks Obinna,

The App Gateway was deleted some time ago, the resource itself might be removed and redeployed several times during development and testing.

If a support ticket with Microsoft has to be raised every single time to remove the hidden resources, that won't be ideal. Is there no way to detach these resources? Scaling the App Gateway to 0 before deleting maybe?
Sai Prasanna Sinde 5,010 Reputation points Microsoft External Staff

2025-04-14T11:15:07.96+00:00

Hi @Mitch Abel

Ideally, you can have multiple instances of a specific Application Gateway deployment in a subnet.

See: Virtual network and dedicated subnet - this means, you should be technically able to deploy a new gateway.

However, it's possible that the residual resources aren't a full pledged app gateway and could be leading to this issue.

May I ask what happens when you delete the subnet?

Can you share the exact error message/ screenshot?

Also, please leverage Azure Powershell / CLI instead of portal.

Refer: https://learn.microsoft.com/en-us/azure/virtual-network/virtual-network-manage-subnet?tabs=azure-powershell#delete-a-subnet

When you deleted the original App gateway, was there a success message or was there any errors?

You can find this information from the resource group's Activity logs

Filter for the right time stamp and you should see Delete Operation on App Gateway.

Can you confirm if the "Status" of this operation shows as "Succeeded"?

Kindly let us know if the above helps or you need further assistance on this issue.
Venkat V 1,390 Reputation points Microsoft External Staff

2025-04-16T06:05:57.78+00:00

Hi @Mitch Abel

I just wanted to follow up and see if you had a chance to review my response to your question. Please let us know if it was helpful, and feel free to reach out if you have any further queries.

Answer 1

Hi @Mitch Abel,

Is there no way to detach these resources?

As there is no way to detach or delete a resource stuck in the Provisioning state, only the support team can access and remove such resources.

If the subnet remains locked even after deleting the application gateway and waiting, check the subnet status using the cmdlet below. It will display the current state. If the resource has failed in the 'Provisioning' state, only the support team can delete it.

az network vnet subnet show -g MyResourceGroup -n MySubnet --vnet-name MyVNet  

az resource show

Reference: az resource show

To prevent this from happening again, ensure that resources are properly managed and cleaned up after deployments. Always check for any dependencies or connected devices before deleting a resource to avoid such conflicts.

I hope this helps to resolve your issue. Please feel free to ask any questions if the solution provided isn't helpful.

If this answer helped you, please don’t forget to upvote and mark it as accepted to help others in the community.

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Virtual Network unable to remove/delete Connected devices

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