Dell PowerEdge 2500 - Manual (Page 19)

Back-Panel Features
Figure 2-3 shows the back-panel features of the non-redundant AC power version of the system.
Figure 2-3. Back-Panel Features
SCSI Hard-Disk Drive Indicator Codes
If you have the integrated RAID controller activated, or an optional PERC 3/Di controller is installed in the system, three indicators on each of the hard-disk drive
carriers provide information on the status of the SCSI hard-disk drives (see
Table 2-1 ). The SCSI backplane firmware controls the drive online and drive failure
indicators.
Figure 2-4. Hard-Disk Drive Indicators