The DCS3700 storage enclosure
The DCS3700 is a 4U rack-mountable storage enclosure that supports two environmental service modules (ESMs). The standard DCS3700 ESMs have two 6 Gbps x 4 SAS host interface ports. The supported host interface card is a four-port 6 Gbps SAS adapter.
The DCS3700: a front view
Figure 1. A front view of the DCS3700
Figure 2 shows a DCS3700 enclosure without the front bezel in place.
Figure 2. Components of the DCS3700 storage enclosure
The DCS3700: a back view
Figure 3. A back view of the DCS3700
The DCS3700: drive drawer mapping
Figure 4. Drive drawer mapping for the DCS3700 
The DCS3700: disk drive mapping
The DCS3700 maps installed disk drives in the order shown in the following figure.
The drives are ordered as follows:
- Front-row drives: 1, 4, 7, 10
- Middle-row drives: 2, 5, 8, 11
- Last-row drives: 3, 6, 9, 12
Figure 5. Disk drive mapping for the DCS3700 
In a 4U building-block configuration, the two SSDs go in Enclosure 1, which is at the bottom of the rack.
SSD 1 goes in Slot 3 in Drawer 1 (at the top of Enclosure 1).
SSD 2 goes in Slot 12 in Drawer 5 (at the bottom of Enclosure 1).
The placement of the two SSDs is shown in the following figure.
Figure 6. DCS3700 disk population with 58 HDDs and two SSDs 