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We do not recommend using virtual Fibre Channel (vFC) with PowerStore. If direct-attached storage is required for a Hyper-V VM, we recommend using in-guest iSCSI.
vFC requires a more complicated setup than in-guest iSCSI, and vFC can be difficult to configure and troubleshoot.
There is also limited support for a vFC configuration with PowerStore.
Note: A security parameter might be required to be disabled for a guest VM configured to use vFC adapters. See this Microsoft KB for more information.
To map WWNs to a new host (or a VM) in PowerStore Manager, the WWNs must be active. The Microsoft implementation of vFC assigns two virtual-WWN-address sets to each vFC adapter as shown in the following figure. Address set B is offline by default. The VM alternates between address set A and B when the VM fails over or live migrates. Only one set can be active at a time.
PowerStore Manager does not provide a way to map WWNs to a host or VM if the WWNs are offline. The vFC volume mapped to a VM can only be configured with half the WWNs (the active set but not the standby set). As a result, if the VM switches to the standby address set for any reason, the VM loses connectivity to the vFC volume. This occurrence causes a service interruption.
In this example, the ports ending in 04 and 06 (set A) are active. The ports ending in 05 and 07 (set B) are inactive. When the VM moves to another host, the states reverse: ports 04 and 06 (set A) become inactive, and 05 and 07 (set B) become active.
There are limited use cases for vFC with PowerStore. These use cases require the administrator to acknowledge and work around the inability to assign both sets of vFC WWN addresses to a VM.