Disk-array enclosure
VNX5500 Hardware Information Guide 83
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 connect to the DPE and other DAEs with 6-Gb/s
SAS cables. The cables connect the LCCs 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 platform’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’s 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 Figure 72 on page 82, an enclosure ID
1
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.
2U, 25 (2.5-inch) DAE AC power supply/cooling module
Figure 73 shows an example of the 2U, 25 (2.5-inch) DAE AC power supply/cooling
module with an AC (power in) recessed connector (plug) and status LEDs.
Figure 73 Example of a 2U, 25 (2.5-inch) DAE AC power supply/cooling module (power in) recessed
connector (plug) and status LEDs
1. The enclosure ID is sometimes referred to as the enclosure address (EA).
Latch handle
Power fault LED Power on LED
Power supply in
VNX-000279