IBM System Storage Subsystem DS5020 - Manual (Page 136)

Table 15. Rear controller LEDs, controls, and connectors
LED Normal Status Problem Status
Service Action Allowed (OK to
Remove) Off On
Service Action Required
(Fault) Off On
Cache Active On - Data is in cache
Off - Caching is turned off. No
data in cache
Not applicable
Diagnostic On - Seven-segment LEDs
indicate diagnostic code
Off - Seven-segment LEDs
indicate enclosure ID
Not applicable
Heartbeat Blinking Off
Host Channel Speed - L1 See Table 16 on page 107.
Host Channel Speed - L2 See Table 16 on page 107.
Ethernet Link Speed On - 1 Gbps
Off - 100 Mbps
Not applicable
Note: The iSCSI ports have the same LEDs as the management Ethernet ports. As
with the Ethernet port LEDs, the iSCSI port LEDs represent link speed and
link activity.
Heartbeat
LED Diagnostic
LED
Cache
active
LED
Service
action
required
LED Service
action
allowed
LED
Host channel
speed - L1 LED Drive channel
port bypass LED
Drive channel
speed LED
Ethernet link
activity LED
Ethernet link
speed LED
Host channel
speed - L2 LED
Figure 71. LEDs, controls, and connectors of controllers with two standard Fibre Channel
host expansion channels and two optional iSCSI host expansion channels
106 IBM System Storage DS5020 Storage Subsystem: Installation, User’s, and Maintenance Guide