Unable to delete AKS load balancer where VMSS is already deleted

Question

Hi team,

I cannot delete the "kuebernetes" load balancer from my deleted AKS clusters.
I also cannot delete the backpools.

I don't have any support plan so I cant file a ticket. Can I get some support to delete the resource please. I am still being charged.

Answer 1

Hi Chi Sang Hui,

This issue occurs when an Azure Kubernetes Service (AKS) cluster is deleted, but the associated Azure Load Balancer ("kubernetes") and backend pools remain in the resource group. This is often due to orphaned network interfaces (NICs) or lingering dependencies.

Steps to resolve:

Check and delete orphaned NICs

The load balancer might still be associated with orphaned NICs from the deleted Virtual Machine Scale Set (VMSS). Run the following command to list NICs in the resource group:

az network nic list --resource-group <RESOURCE_GROUP_NAME> --query "[].id" -o tsv

If any NICs exist, delete them:

az network nic delete --ids <NIC_ID>

Remove backend pools manually

If the backend pools are still associated with deleted VMSS instances, remove them manually:

az network lb address-pool list --resource-group <RESOURCE_GROUP_NAME> --lb-name kubernetes

If any backend pools exist, delete them:

az network lb address-pool delete --resource-group <RESOURCE_GROUP_NAME> --lb-name kubernetes --name <POOL_NAME>

Delete the load balancer Once dependencies are removed, delete the load balancer:

az network lb delete --resource-group <RESOURCE_GROUP_NAME> --name kubernetes

Check for other dependencies

Verify if any public IPs, managed identities, or NSGs related to the AKS cluster remain in the resource group and delete them. 

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Thank You.

Answer 2

Hi Geethasri,

Thank you for the answer.

1. I dont have any NICs remaining in the resource group and the result is empty when running
   az network nic list
2. There are 2 backend pools in the kubernetes lb but when I tried to delete them it errors with Failed to delete load balancer backend pool 'kubernetes'. Error: Cannot remove backend address pool kubernetes from load balancer since it is in use by virtual machine scale set /subscriptions/xxx. Where the vmss is obviously deleted already.

Attached are the only remaining resources in the resource group.

I believe there are some dangling resource relationships that needs Microsoft team to resolve, can I get permission to open an one-off ticket?