Administrator Guide

Fault Domains for SCv2000 Series Storage Systems
The Storage Center handles all fault domain creation and modication on SCv2000 series storage systems.
Depending on the hardware conguration, the following fault domains are automatically created on SCv2000 series storage systems:
• For SCv2000 series storage systems with Fibre Channel HBAs, two fault domains are created for the Fibre Channel ports.
• For SCv2000 series storage systems with iSCSI HBAs, two fault domains are created for the iSCSI ports.
• For SCv2000 series storage systems with SAS HBAs, four fault domains are created for the SAS ports.
• Fault domains are automatically created for Flex/Embedded Ethernet ports.
NOTE: Additional front-end fault domains cannot be created on SCv2000 series storage systems. In addition, existing fault
domains cannot be modied or deleted on SCv2000 series storage systems.
Fault Domains for SCv3000 Series Storage Systems
The Storage Center handles all fault domain creation and modication on SCv3000 series storage systems.
Depending on the hardware conguration, the following fault domains are automatically created on SCv3000 series storage systems:
• For SCv3000 series storage systems with Fibre Channel HBAs, two fault domains are created for the Fibre Channel ports.
• For SCv3000 series storage systems with iSCSI HBAs, two fault domains are created for the iSCSI ports.
• For SCv3000 series storage systems with SAS HBAs, four fault domains are created for the SAS ports.
• For SCv3000 series storage systems with iSCSI mezzanine cards, two fault domains are created for the iSCSI ports.
• For SCv3000 series storage systems with iSCSI mezzanine cards and iSCSI HBAs, four fault domains are created for iSCSI ports
NOTE
: Additional front-end fault domains cannot be created on SCv3000 series storage systems. In addition, existing fault
domains cannot be modied or deleted on SCv3000 series storage systems.
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 dierent fault domain, its control port changes. This change disrupts any service initiated through the previous
control port. If an iSCSI port moves to a dierent fault domain, you must recongure 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.
Fault Domains in Legacy Mode
In Legacy Mode, each pair of primary and reserved ports are grouped into a fault domain. The fault domain determines which ports are
allowed to fail over to each other.
The following requirements apply to fault domains in legacy mode on a dual-controller Storage Center:
• A fault domain must contain one type of transport media (FC or iSCSI, but not both).
• A fault domain must contain one primary port and one reserved port.
Storage Center Maintenance
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