CreateOrUpdate: context deadline exceeded , while removing data disk

Question

I'm getting context deadline exceeded error while trying to detach disks from azure virtual machine.

Answer 1

Hi,

Have you tried force detach? You may use command similar to below in Azure Cloud Shell:

az vm disk detach --resource-group my_resource_group --vm-name vm --name managed_disk_name --force-detach

Please click Accept Answer and upvote if the above was helpful.

Thanks.

-TP

Answer 2

context deadline exceeded during disk detach usually indicates the operation is timing out or blocked by an underlying lease or attachment state. Use the supported detach paths and then verify the disk/VHD lease is released.

1. Detach the data disk from the VM (portal)
   • In Azure portal, go to Virtual Machines.
   • Select the VM that has the data disk.
   • Under Settings, select Disks.
   • On the Disks pane, to the far right of the data disk to detach, select the detach button (X icon).
   • Select Save at the top of the page.
   • The disk remains in storage but is no longer attached to the VM.
2. Detach the data disk from the VM (PowerShell)
   • Make sure nothing is actively using the disk.
   • Run:

          $vm = Get-AzVM -ResourceGroupName "myResourceGroup" -Name "myVM"
          Remove-AzVMDataDisk -VM $vm -Name "myDisk"
          Update-AzVM -ResourceGroupName "myResourceGroup" -VM $vm
     

   • The disk stays in storage but is detached from the VM.
   • In regions where lower detach latency is available, call Remove-AzVMDataDisk explicitly to benefit from reduced latency.
3. If the error occurs while deleting the underlying VHD/blob
   • Azure prevents deletion of a disk/blob that is still attached or leased.
   • Ensure the disk is detached as above, then wait a few minutes for the lease to clear.
   • To verify:
     • In the portal, browse to the storage account → container → blob (VHD).
     • In Blob properties, confirm Lease Status is Unlocked or Available.
   • If the lease is still active, re-check that the disk is not attached to any VM and retry after a short delay.
4. If the VM deployment or update is failing due to a problematic disk
   • For API-based operations, set the toBeDetached flag for the failing data disk via the Compute REST API, or remove the failing data disk from the VM payload, then PATCH the VM:

          GET https://management.azure.com/subscriptions/{subscriptionId}/resourceGroups/{resourceGroupName}/providers/Microsoft.Compute/virtualMachines/{vmName}?$expand=instanceView&api-version=2019-03-01
     

     Modify the disk section (set toBeDetached = true or remove the disk), then:

          PATCH https://management.azure.com/subscriptions/{subscriptionId}/resourceGroups/{resourceGroupName}/providers/Microsoft.Compute/virtualMachines/{vmName}?api-version=2019-03-01
     

   • This clears failing disk attachments that can cause long-running or timed-out operations.

If context deadline exceeded persists, validate that:

• The disk is not being used by the guest OS (no active I/O).
• The VM is in a healthy state (not stuck in failed updates).
• The VHD/blob lease has transitioned to Unlocked/Available before attempting deletion or further operations.

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References:

• How to detach a data disk from a Windows virtual machine
• Tutorial: Manage disks with Azure PowerShell
• Troubleshoot storage resource deletion errors
• Troubleshoot virtual machine deployment due to detached disks
• Use the Azure portal to manage disks on the VMs on your Azure Stack Edge Pro GPU