Dell Storage Manager 2020 R1 Administrator's Guide

Fault Domains in Virtual Port Mode

In virtual port mode, fault domains group front-end ports that are connected to the same Fibre Channel fabric or Ethernet network. All ports in a fault domain are available for I/O. If a port fails, I/O is routed to another port in the fault domain.

The following requirements apply to fault domains in virtual port mode:

• Fault domains are created for each front-end Fibre Channel fabric or Ethernet network.
• A fault domain must contain a single type of transport media (FC or iSCSI, but not both).
  CAUTION:For iSCSI only, servers initiate I/O to iSCSI ports through the control port of the fault domain. If an iSCSI port moves to a different fault domain, its control port changes. This change disrupts any service initiated through the previous control port. If an iSCSI port moves to a different fault domain, you must reconfigure the server-side iSCSI initiators before service can be resumed.
• For each fault domain, it is a best practice to connect at least two cables from each controller to the Fibre Channel fabric or Ethernet network.