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Administration best practices
19 Dell EMC PowerVault ME4 Series and Microsoft Hyper-V | 3921-BP-WS
3.4.2 Mixed transports
There is limited Microsoft support for using mixed transports to present an ME4 Series LUN to a Windows
Server Hyper-V host or cluster node, and this not recommended as a best practice. In each a Hyper-V cluster
environment, all nodes should be configured to use a common transport (FC, iSCSI, or SAS).
There are some use cases where using mixed transports may be necessary, such as when migrating the
overall environment from one type of transport to another, and both transports need to be available to a host
during a transition period. If mixed transports must be used, use a single transport for each LUN mapped to a
Hyper-V host or node.
The following mapping is recommended:
• LUN1 is mapped to host 1 using FC only (with MPIO)
• LUN2 is mapped to host 1 using iSCSI only (with MPIO)
The following mapping is not recommended:
• LUN1 is mapped to host 1 using both FC and iSCSI paths
Each transport by itself should provide adequate bandwidth and MPIO resiliency. Configuring a LUN to use
multiple transports increases design complexity unnecessarily and can introduce unpredictable service-
affecting I/O behavior in path failure scenarios.
3.4.3 MPIO best practices
Windows Server and Hyper-V natively support MPIO by means of the built-in Device Specific Module (DSM)
that is bundled with the OS. This DSM is fully supported with ME4 Series arrays.
Windows and Hyper-V hosts default to the Round Robin with Subset policy with ME4 Series storage, unless a
different default MPIO policy is set on the host by the administrator. Round Robin with Subset is typically the
best MPIO policy for Hyper-V environments.
Verify MPIO settings (Microsoft DSM shown)