Administrator Guide

• The reserved port must be located on a dierent controller than the primary port.
NOTE: For a single-controller Storage Center, only one fault domain is required for each transport type (FC or iSCSI) because
there are no reserved ports.
Failover Behavior
Legacy mode, ALUA port mode, and virtual port mode behave dierently during failure conditions because they use dierent mechanisms
to provide fault tolerance.
Table 11. Front-End I/O Ports Failover Behavior
Scenario Virtual Port Mode Legacy Mode ALUA Port Mode
Normal operating
conditions
All ports are active and pass I/O.
• Primary ports pass I/O.
• Reserved ports remain in a
standby mode until a controller
failure.
• Active/Optimized ports pass
I/O.
• Standby ports remain in a
standby mode until a controller
or port failure.
A controller fails in a dual-
controller Storage Center
Virtual ports on the failed
controller move to physical ports
on the functioning controller.
Primary ports on the failed
controller fail over to reserved
ports on the functioning controller.
Active/Optimized ports on the
failed controller fail over to the
Standby ports on the functioning
controller.
A single port fails (single- or
dual-controller Storage
Center)
An individual port fails over to
another port on the same
controller in the same fault
domain.
NOTE: To support port
level failover, a controller
must have at least two
ports in the same fault
domain using the same
transport media, such as
FC or iSCSI.
The port does not fail over
because there was no controller
failure. If a second path is available,
MPIO software on the server
provides fault tolerance.
The port fails over to the Standby
port on the functioning controller.
Managing Front-End I/O Port Hardware
Front-end FC and iSCSI ports can be renamed and monitored with threshold denitions. iSCSI ports can be assigned network conguration
and tested for network connectivity.
NOTE
: For user interface reference information, click Help.
Rename a Front-End I/O Port
Set a display name for a physical or virtual I/O port to make it more identiable.
1 If you are connected to a Data Collector, select a Storage Center from the drop-down list in the left navigation pane.
2 From the SYSTEM menu, select Ports.
The Ports view is displayed.
3 Click the Front End Ports tab.
4 Select the I/O port, then click (Edit).
The Edit Port dialog box opens.
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Storage Center Maintenance