IBM Partner Pavilion DS4100 manual DS4000 EXP100 redundant loop configuration

Left ESM board Right ESM board

Input

Output

3

Output

Last expansion unit

4

Second expansion unit

6

1	2	Loop B Fibre Channel
		interface cable
Loop A Fibre Channel

interface cable

First expansion unit

5

DS4100 storage server with two RAID controllers

f10ug048

Figure 54. DS4000 EXP100 redundant loop configuration

To create the redundant loop shown in Figure 54, you would perform the following steps:

1.Make two fibre-channel connections from the First expansion unit to the Second expansion unit (connections 1 and 2).

2.Make two fibre-channel connections from the Second expansion unit to the Last expansion unit (connections 3 and 4). Currently, you can connect up to three DS4000 EXP100s together in a redundant drive loop. Contact your IBM support representative for information about the availability of future support for connecting more than three DS4000 EXP100 units.

3.Make a fibre-channel connection from the storage server drive port to the OUT port in the left ESM of the First expansion unit in the redundant drive loop (connection 5).

4.Make a fibre-channel connection from the storage server drive port to the IN port in the right ESM of the Last expansion unit in the redundant drive loop (connection 6).

IBM SATA disk drives are dual-ported, providing individual access from two fibre-channel loops to the same disk drive. When configuring the ESMs, configure the second ESM the same way that you configured the first ESM. Refer to the DS4100 Fibre Channel Cabling Instructions for more information about dual-loop support and implementation.

Each ESM on the DS4000 EXP100 has an SFP module input port and an SFP module output port. As you cable DS4000 EXP100s together, connecting input ports to output ports can improve diagnostic capability. Refer to the DS4100 Storage Server Fibre Channel Cabling Instructions for cabling connections between input and output ports.

60IBM TotalStorage DS4100 Storage Server: Installation, User’s, and Maintenance Guide