Dell EqualLogic PS Series Hardware Owner's Manual page 24

PS6610 Hardware Owner's Manual
LED Name State
Off
Steady red
ERR
Blinking red
Off
PWR
On (steady
green)
Identify Control Module Failures
You can identify a failure in a control module by:
• LEDs on the control module itself. See
• Messages on the console, in the event log, or in the Group Manager GUI Alarms panel.
• Group Manager GUI and CLI output. The Member Controllers window or the
show controllers
When viewed from the rear of the array, CM0 is on the left and CM1 is on the right.
If a control module fails, contact your PS Series support provider for a replacement.
About Failover Behavior
In a dual control module array, only one control module is active (processing network I/O and
performing storage functions) at one time. Each control module stores recently used data.
For redundancy, the cache on the secondary control module mirrors the data that is stored in the cache
on the active control module.
The active control module can use the network interfaces of the secondary control module for failover
if a cable is connected from the corresponding port on the secondary control module to a functioning
network switch.
The management ports on the control modules do not fail over if one control module fails.
Note:
Therefore, if you are using a dedicated management network, make sure the management ports on
both control modules are connected to the management network.
A PS Series array provides the following types of network failure protection:
• Vertical failover. In a dual control module array, a network port on the active control module can
fail over to the same network port on the other (secondary) control module if a network path fails.
For example, if Ethernet 0 on CM0 loses connectivity (switch 0 fails), Ethernet 0 on CM1 cache is
enabled and utilized. See
• Control module failover. In a dual control module array, if the active control module fails, the
secondary control module automatically takes over and becomes active.
If a cable is connected to a network port on the newly active control module, network I/O can
switch to its network interface. Depending on circumstances, network I/O might instead continue
through the previously active control module. (For example, the control module that becomes
active can use either its own local network interface, or the network interface on the previously
active control module.)
18
Description
Normal operation or no power
Array is starting up, in error condition, in Standby mode, or returning from
Standby mode.
Array is entering power standby mode because the Standby On/Off button
was pressed.
No power
Power/OK
Interpreting Control Module LEDs on page
command output shows the control module status
Dual Controller Configuration on page 16
3 Control Module Maintenance
16.
member select
.
not installed
for details.