Lenovo ThinkSystem D4390 Hardware Installation And Maintenance Manual page 11

Figure 1-3 below is the rear view of the chassis showing PSU, DC-DC modules and ESM canisters.
Figure 1-3: D4390 System Rear View
Figure 1-4 through Figure 1-6 below show the LED information on the D4390 JBOD.
Figure 1-4: D4390 System LEDs
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