Live Migration with Platform9 Managed OpenStack

Platform9 Managed OpenStack supports live migration on KVM.

What is live migration?

Live migration means migrating or transferring a virtual machine (VM) from one physical hypervisor (host) to another, while the VM is still running. The VM might have applications running on it.

The VM or application downtime during a live migration is very small or negligible.

The host from which a live or running VM is transferred, is called the source host. The host to which the running VM is transferred, is called the destination host.

When is live migration performed?

Live migration is performed in the following scenarios.

Prepare hosts for live migration

You must be an administrator to perform live migration.

The following steps must be performed on the source host and the destination host before you start with the live migration.

Once the host preparation is complete, you are ready to perform a live migration of VM instances on Platform9 Managed OpenStack.

How to perform a live migration?

Live migration can be done in one of the following two ways.

The steps for each of the above-mentioned ways are explained in the sections below.

Live Migration using Clarity

Live migration is a simple two-step process when it is performed by using the Clarity UI.

Follow the steps given below to perform live migration through the Clarity UI.

  1. Log in to Clarity as an administrator.
  2. Click Instances and select the check box for the instance to migrate.
  3. Click More on the toolbar above the list of instances.
  4. Click the Migrate Instance option.
  5. Select the host to migrate the instance and click Migrate VM.

When the migration is successful, the destination host name appears as the host for the migrated VM instance.

Live Migration using OpenStack (CLI)

Run the following command on the OpenStack CLI, to perform live migration.

openstack server migrate --live <destination-host> <vm-name>

April 13, 2017