Dell EqualLogic PS6210 Hardware Owner's Manual page 22

PS6210 Hardware Owner's Manual
Only one control module is active (providing disk access and serving network traffic) at one time. The
secondary (redundant) control module mirrors cache data from the active control module. If the active
control module fails, all functions of the primary controller transfer to the secondary.
Dual Controller Configuration
A dual control module configuration eliminates a single point of failure in the array. If the active
control module fails, the secondary control module takes over automatically with no interruption of
service. This automatic transition gives you time to replace the failed control module while your
volumes and data remain accessible.
In addition, a dual control module configuration supports a feature called vertical failover. An Ethernet
port on the active control module can fail over to the same Ethernet port on the secondary control
module if a network path fails.
Figure 16: Recommended Network Configuration to Support Vertical Failover
• If a network port is available for failover on either control module, but is not currently in use, its
LEDs will not be lit.
• Vertical failover is transparent to applications.
Interpreting Control Module LEDs
Control modules have the following LEDs:
• The Ethernet ports and the Management port each have LEDs that indicate the port's status and
activity. See Table
• Below the release latch is a column of three LEDs that indicate the status of the entire control
module. See Table 7.
16
Figure 16 shows a recommended configuration for vertical failover.
6.
3 Maintaining Control Modules