Managing Block Storage Scheduling

Administrators have control over which volume back end your volumes reside on. You can specify affinity or anti-affinity between two volumes. Affinity between volumes means that they are stored on the same back end, whereas anti-affinity means that they are stored on different back ends.

You can create the following volumes:

  • Create a new volume on the same back end as Volume_A:

      $ cinder create --hint same_host=Volume_A-UUID SIZE
    
  • Create a new volume on a different back end than Volume_A:

      $ cinder create --hint different_host=Volume_A-UUID SIZE
    
  • Create a new volume on the same back end as Volume_A and Volume_B:

      $ cinder create --hint same_host=Volume_A-UUID --hint same_host=Volume_B-UUID SIZE
    

    Or:

      $ cinder create --hint same_host="[Volume_A-UUID, Volume_B-UUID]" SIZE
    
  • Create a new volume on a different back end than both Volume_A and Volume_B:

      $ cinder create --hint different_host=Volume_A-UUID --hint different_host=Volume_B-UUID SIZE
    

    Or:

      $ cinder create --hint different_host="[Volume_A-UUID, Volume_B-UUID]" SIZE