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Data Progression and Hyper-V
39 Dell EMC SC Series: Microsoft Hyper-V Best Practices | CML1009
SC Series arrays do provide some protections against this scenario. For example, when replicating a volume
from one SC Series array to another, by default the replicated data is placed into the lowest tier. However, if
performing a file level copy in Hyper-V at the host or VM level, new writes will occur in the highest tier allowed
by the storage profile that is applied to the target volume, which will usually be the Recommended (All Tiers)
profile.
To avoid exhausting tier 1 capacity when copying or migrating a large amount of data, consider the following
options:
• Option 1: Modify the storage profile for the target CSV or other volume to temporarily exclude tier 1.
Then copy the data. Then change the storage profile back again. This assumes that any workloads
that use the target volume during the copy operation are not negatively impacted by lack of tier 1
performance.
• Option 2: Copy data in smaller batches. Monitor the capacity status of tier 1 and allow Data
Progression to digest and move the data to a lower tier to free up space in tier 1 before copying more
data.
• Option 3: Create a new CSV or other volume as a target for the copied or migrated data and assign a
storage profile that excludes tier 1. Once the data is copied, then adjust the storage profile to include
tier 1 if necessary.