Dell EMC VxFlex Ready Node, Руководство пользователя

Страница: 63 / 354

Figure 11 V-Tree diagram
V-Tree migration
V-Tree refers to Volume Tree and all the snapshots under. Migrating a V-Tree allows
you to move the V-Tree to a Storage Pool with a different storage tier.
Migrating a V-Tree frees up space in the source Storage Pool. For example, from an
HDD Storage Pool to an SSD Storage Pool or different attributes (for example, from
thin to thick). For more information see "Volume Tree" in the
Getting to Know Guide .
There are several reasons why you might require moving a volume which include:
l
Move to different Storage Pool's volumes to a different performance tier
l
Move to different Storage Pool or Protection Domain due to multi-tenancy
l
Move from Storage Pool or Protection Domain to shrink a system
l
Change from thin to thick or visa versa
l
Change from Multi Granularity to Fine Granularity
l
Drain a protection domain, maintain it and then fill it back up.
When running V-tree, you can run other tasks such as snapshots creation and deletion
and maintenance mode
Note: Snapshots are not allowed when migrating from Multi Granularity to Fine
Granularity.
When the user requests a V-Tree migration, the MDM first estimates whether the
destination Storage Pool has enough capacity for the migration to complete
successfully, based on the MDM's information of the V-Tree's current capacity. If
there is insufficient capacity at the destination based on that estimate, migration does
not start. (An advanced option allows you to force the migration even if there is
insufficient capacity at the destination, with the intention to increase the capacity as
required during the migration.) Note that the MDM does not actually reserve the
estimated capacity at the destination (since the source volume's capacity can grow
Architecture
Dell EMC VxFlex Ready Node AMS User Guide 63