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SC Series snapshots and Hyper-V
36 Dell EMC SC Series: Microsoft Hyper-V Best Practices | CML1009
As a best practice, add the controller SN to the name of the gold image volume.
Add the controller serial number to the volume name
As new servers are deployed from View Volumes, alternate between gold image source volumes so that each
controller head stays balanced with roughly the same number of volumes.
3.6 SC Series snapshots and Hyper-V VM migration
Microsoft provides native tools to move or migrate VMs with Windows Server 2012 Hyper-V and newer, so
there are fewer use cases for using SAN-based snapshots to move VMs. When a guest VM is live migrated
from one node to another node within the same Hyper-V cluster configuration, no data needs to be copied or
moved because all nodes in that cluster have shared access to the underlying cluster shared volumes (CSV).
However, when an administrator needs to migrate a guest VM from one host or cluster to another host or
cluster, the data (the virtual hard disks) must be copied to the target host or cluster, and this will consume
network bandwidth and may require significant time if the virtual hard disks are extremely large. This can also
consume additional SAN space unnecessarily because another copy of the data is created.
When moving VMs to another host or cluster, it may be much quicker to leverage the SC Series array to
simply unmap the host volumes containing the VM configuration files and virtual hard disks and map them to
the new target host or cluster. This can also be done using a using a View Volume from a point-in-time
snapshot of the volume.
While this might involve a small amount of down time for the VM being moved during a maintenance window,
it might be a much more practical approach than waiting for a large amount of data to copy over the network,
consuming additional SAN space unnecessarily.
To avoid or minimize down time when multiple SC Series are involved, consider leveraging SC Series
replication and Live Volume, or SC Series Federation features. For more information on replication between
SC Series including Live Volume with automatic failover for Microsoft, see the Dell EMC SC Series
Synchronous Replication and Live Volume guide.