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PowerStore supports virtual Fibre Channel (vFC), but there are limitations. If you require direct-attached storage for a Hyper-V guest VM, use in-guest iSCSI (preferred).
vFC is a more complicated setup than in-guest iSCSI. vFC is more difficult to configure and troubleshoot.
PowerStoreOS versions before 3.0 offer limited support for vFC. PowerStoreOS versions before 3.0 do not support mapping standby (offline) virtual WWNs to a VM.
Note: The use of vFC adapters may require disabling a security parameter. See this Microsoft KB for more information.
The Microsoft implementation of vFC assigns two virtual WWN address sets to each vFC adapter on a guest VM, as shown in Figure 19. Address set B is offline by default. The guest 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.
With PowerStoreOS versions before 3.0, PowerStore Manager does not provide a way to map WWNs to a guest VM if the WWNs are offline. Only half of the WWNs can be mapped (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.
If you configure vFC with PowerStoreOS 3.0 and newer, make sure to map set A WWNs (active/online) and manually map set B WWNs (standby/offline). This configuration preserves vFC connectivity if a guest VM fails over or live-migrates.
In this example, the ports ending in 04 and 06 (set A) are active/online. The ports ending in 05 and 07 (set B) are standby/offline. If the guest VM live migrates or fails over to another Hyper-V node, the state of the address sets reverse. Ports 04 and 06 (set A) go offline, and ports 05 and 07 (set B) become active.
There are limited use cases for vFC with PowerStore. The use cases for vFC are like the use cases for in-guest iSCSI and pass-through disks. See In-guest iSCSI, vFC, and pass-through disk use cases for more information.
vFC supports MPIO. If MPIO is wanted, install and configure the MPIO feature on the guest VM.