Dell SC8000, Руководство по развертыванию

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Front-End Connectivity Modes
Dell Compellent 97
Virtual Port Mode
Virtual port mode provides port and controller redundancy by connecting multiple active
ports to each Fibre Channel or Ethernet switch.
In virtual port mode, each physical port has a WWN (World Wide Name), and is also
assigned an additional virtual WWN. Servers target only the virtual WWNs. During
normal conditions, all ports process IO. If a port or controller fails, a virtual WWN can be
moved to another physical WWN in the same fault domain. When the failure is resolved
and ports are rebalanced, the virtual port returns to the preferred physical port.
Virtual port mode provides the following advantages over legacy mode:

Increased performance : Because all ports are active, additional front ‐ end bandwidth is
available without sacrificing redundancy.

Improved redundancy : Ports can fail over individually instead of by controller.

Simplified iSCSI configuration : Each fault domain has an iSCSI control port that
coordinates discovery of the iSCSI ports in the domain. When a server targets the iSCSI
port IP address, it automatically discovers all ports in the fault domain.
Fault Domains in Virtual Port Mode
Fault domains group front ‐ end ports that are connected to the same Fibre Channel fabric
or Ethernet network. Ports that belong to the same fault domain can fail over to each other
because they have the same connectivity.
The following requirements apply to fault domains in virtual port mode:

A separate fault domain must be 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).

Dell Compellent recommends configuring at least two connections from each controller
to each Fibre Channel or Ethernet network (fault domain).
Requirements for Virtual Port Mode
The following requirements must be met to configure a Storage Center in virtual port
mode.
Note: Dell Compellent strongly recommends using virtual port mode unless the
network environment does not meet the requirements for virtual port mode.
Requirement Description
License The Storage Center must be licensed for virtual port mode.
Switches Front ‐ end ports must be connected to Fibre Channel or Ethernet switches;
servers cannot be directly connected to controller front ‐ end ports.