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EMC VNXe3100 Hardware Information Guide
Overview
Rear view
On the rear, a 2U, 25 (2.5-inch) DAE includes the following hardware components
(
):
◆
Two 6-Gb/s SAS LCCs (A and B)
◆
Two power supply/cooling modules
6-Gb/s SAS LCC
The 6-Gb/s SAS LCC supports, controls, and monitors the DAE, and is the primary
interconnect management element (
). Each LCC includes connectors
for input and output to downstream devices.
As described previously, the LCCs in a DAE connects to the DPE and other DAEs with
6-Gb/s SAS cables. The cables connect the LCCs in a system in a daisy-chain topology.
Internally, each DAE LCC connects to the drives in its enclosure in a point-to-point fashion
through a switch. The LCC independently receives and electrically terminates incoming
signals. For traffic from the system’s storage processors, the LCC switch passes the signal
from the input port to the drive being accessed; the switch then forwards the drive output
signal to the port.
Note: If the target drive is not in the LCC enclosure, the switch passes the input signal
directly to the output port.
Each LCC independently monitors the environmental status of the entire enclosure, using
a microcomputer-controlled monitor program. The monitor communicates the status to
the storage processor, which polls disk enclosure status. LCC firmware also controls the
SAS PHYs and the disk-module status LEDs.
As shown in
, an enclosure ID
9
indicator is located on each LCC. Each
LCC also includes a bus (back-end port) identification indicator. The SP initializes the bus
ID when the operating system is loaded.
Disk drive fault (location 4)
Amber
On
Fault has occurred
—
Off
No fault has occurred
Disk drive on/activity
(location 5)
Blue
On
Powering and powered up
Blinking
Disk drive activity
Table 22 Example of a 2U, 25 (2.5-inch) DAE and the disk drive LEDs (continued)
LED
Color
State
Description
9. The enclosure ID is sometimes referred to as the enclosure address (EA).
