16.3.6. Checking migration status

Migration involves several state transitions before migration is complete. During a healthy migration, the migration state typically transitions as follows:

  1. Queued: The Compute service has accepted the request to migrate an instance, and migration is pending.
  2. Preparing: The Compute service is preparing to migrate the instance.
  3. Running: The Compute service is migrating the instance.
  4. Post-migrating: The Compute service has built the instance on the destination Compute node and is releasing resources on the source Compute node.
  5. Completed: The Compute service has completed migrating the instance and finished releasing resources on the source Compute node.

Procedure

  1. Retrieve the list of migration IDs for the instance:

    $ nova server-migration-list <instance>
    
    +----+-------------+-----------  (...)
    | Id | Source Node | Dest Node | (...)
    +----+-------------+-----------+ (...)
    | 2  | -           | -         | (...)
    +----+-------------+-----------+ (...)

    Replace <instance> with the name or ID of the instance.

  2. Show the status of the migration:

    $ nova server-migration-show <instance> <migration_id>
    • Replace <instance> with the name or ID of the instance.
    • Replace <migration_id> with the ID of the migration.

      Running the nova server-migration-show command returns the following example output:

      +------------------------+--------------------------------------+
      | Property               | Value                                |
      +------------------------+--------------------------------------+
      | created_at             | 2017-03-08T02:53:06.000000           |
      | dest_compute           | controller                           |
      | dest_host              | -                                    |
      | dest_node              | -                                    |
      | disk_processed_bytes   | 0                                    |
      | disk_remaining_bytes   | 0                                    |
      | disk_total_bytes       | 0                                    |
      | id                     | 2                                    |
      | memory_processed_bytes | 65502513                             |
      | memory_remaining_bytes | 786427904                            |
      | memory_total_bytes     | 1091379200                           |
      | server_uuid            | d1df1b5a-70c4-4fed-98b7-423362f2c47c |
      | source_compute         | compute2                             |
      | source_node            | -                                    |
      | status                 | running                              |
      | updated_at             | 2017-03-08T02:53:47.000000           |
      +------------------------+--------------------------------------+
      ヒント

      The OpenStack Compute service measures progress of the migration by the number of remaining memory bytes to copy. If this number does not decrease over time, the migration might be unable to complete, and the Compute service might abort it.

Sometimes instance migration can take a long time or encounter errors. For more information, see Troubleshooting migration.