Detaching a VM

After the VM is Fully Cached and you want to start the detach process, you need to prepare the VM for detaching from Google Cloud Migrate for Compute Engine (formerly Velostrata). This task moves the VM disks from the Migrate for Compute Engine cache and object store and creates native disks in Google Cloud.

Preparing to detach a VM

To detach a VM, Migrate for Compute Engine deploys an exporter instance to Google Cloud. The exporter continues to synchronize the VM disks until it's detached or manually stopped. After the VM is in the Ready to Detach state you need to schedule downtime for the detach action, rebooting the VM, and changing any network configuration necessary for your application.

The VM must be in the Fully Cached state prior to running the Preparing to Detach task. If the VM is not in the Fully Cached state, migrate the VM storage to the cloud.

When working in cached mode, all data in disks attached to the Migrate for Compute Engine Cloud Extension (CE) is encrypted.

Using the Migrate for Compute Engine vCenter Plugin

  1. In the vSphere Web Client, select the VM.
  2. Right-click on the VM, and then select Velostrata Operations > Migration Operations > Prepare to Detach.
  3. Select a Disk Type, and then click OK. You can monitor the detach progress in the Summary tab.
    Screenshot of monitoring the detachment (click to enlarge)
    Screenshot of monitoring the detachment (click to enlarge)
    The VM is ready to detach when Ready to Detach is shown in the Storage Migration field.
    Screenshot of when the VM is ready to detach (click to enlarge)
    Screenshot of when the VM is ready to detach (click to enlarge)

Detaching the VM

After the Preparing to Detach task completes successfully, you can detach the VM. You must assign a scheduled downtime slot for detaching. Detaching is a sequence in which the VM shuts down, performs necessary last synchronization including adjusting instance size, attaches the native disks to the instance, and starts the instance.

After you detach the VM, perform any required validation that the VM is functioning correctly, and then either clean up or roll back (if you don't want to detach the VM from Migrate for Compute Engine). See more information in the Starting the detach cleanup section on this page.

Using the Migrate for Compute Engine vCenter plugin

  1. In the vSphere Web Client, select the VM.
  2. Right-click on the VM, and then select Velostrata Operations > Migration Operations > Detach.
  3. Optionally, select a new instance type, and then click OK. You can monitor the detach progress from vCenter:
    Screenshot of detachment progress (click to enlarge)
    Screenshot of detachment progress (click to enlarge)
    After the detach process is completed, Detached is shown in the Storage Migration field.

Starting the detach cleanup

After the VM is detached and you finish testing, you can start the detach cleanup. Cleanup marks the VM as unmanaged by Migrate for Compute Engine and removes the VM's data from the cache. If you want to revert back to VMware, you can move the VM back to fully cached.

Use the Migrate for Compute Engine vCenter plugin

  1. In the vSphere Web Client, select the VM.
  2. Right-click on the VM, and then select Velostrata Operations > Migration Operations > Cleanup.
  3. Confirm that you want to clean up by entering the number in red and clicking OK.
  4. If you want to force a cleanup, select Force Clean up. The storage migration state changes to Cleaning Up. After the cleanup process is completed, the VM is no longer managed by Migrate for Compute Engine and is instead managed by vSphere.
    Screenshot of unmanaged state (click to enlarge)
    Screenshot of unmanaged state (click to enlarge)

Cancelling the detach

When the VM is in the Ready to Detach state, or after it's detached and you want to revert to using the Migrate for Compute Engine cache, you can stop or cancel the detach process. Either action deletes the Google Cloud persistent disk created for the detached instance and moves the VM back to being fully cached.

Use the Migrate for Compute Engine vCenter plugin

  1. In the vSphere Web Client, select the VM.
  2. Right-click on the VM, and then select Velostrata Operations > Migration Operations > Cancel Detach.
  3. Type in four digits to confirm that you want to cancel.
    Screenshot of Cancel Detach dialog box(click to enlarge)
    Screenshot of the Cancel Detach dialog box (click to enlarge)
    After you confirm, the storage migration state changes to Cancelling Detach.
    Screenshot of Cancelling Detach status (click to enlarge)
    Screenshot of Cancelling Detach status (click to enlarge)
    When the cancellation is complete, the storage migration state changes back to Fully Cached.