IBM Midrange System DS4000 Series Hardware Manual page 99

Drive channel bypass / EXP bypass (amber)
– Off: Normal status
– On: Drive port bypass problem
Other LEDs
Serviced action allowed / Ready to remove (blue) (see "Enclosure ID" on page 82 for
details)
– Off: Normal status
– On: Safe to remove
Need attention (amber)
– Off: Normal status
– On: Controller needs attention (controller fault or controller is offline)
Caching active (green)
– On: Data in cache
– Off: No data in cache
Ethernet link rate
– Off: 100 Mbps
– On: 1 Gbps BASE-T
Ethernet link activity
– Off: No link established
– On: Link established (blinks off with transmit or receive activity)
Chapter 3. IBM System Storage DS4000 and DS5000 hardware
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