Compaq AA-RHGWB-TE Connecting Two BA356s for Shared Scsi Bus Usage, Callout Number Description

Table 9–1: Hardware Components Used for Configuration Shown in Figure 8–9 and Figure 8–10

Callout Number	Description
1	BN21W-0B Y cable
2	H879-AA terminator
3	BN21K (or BN21L) cablea
4	H885-AA trilink connector

aThe maximum combined length of the BN21K (or BN21L) cables must not exceed 25 meters.

9.4.2.2Connecting Two BA356s for Shared SCSI Bus Usage

When you use two BA356 storage shelves on a shared SCSI bus in a TruCluster configuration, one BA356 must be configured for SCSI IDs 0 through 6 and the other configured for SCSI IDs 8 through 14.

To prepare two BA356 storage shelves for shared SCSI bus usage (see Figure 9–10), follow these steps:

1.Complete the steps of Section 9.4.1.2 for each BA356. Ensure that the personality module address switches on one BA356 are set to select SCSI IDs 0 through 6, and that the address switches on the other BA356 personality module are set to select SCSI IDs 8 through 14.

2.If either of the BA356 storage shelves will be on the end of the SCSI bus, attach an H879-AA terminator to the H885-AA trilink on the DWZZB for the BA356 that will be on the end of the bus.

3.Connect a BN21K or BN21L cable between the H885-AA trilinks.

4.When the KZPSA-BB or KZPBA-CB host bus adapters have been installed:

•If the BA356 storage shelves are on the end of the shared SCSI bus, connect a BN21K (or BN21L) cable between the BN21W-0B Y cables on the host bus adapters. Connect another BN21K (or BN21L) cable between the BN21W-0B Y cable with an open connector and the H8855-AA trilink (on the BA356) with an open connector.

•If the BA356s are in the middle of the shared SCSI bus, connect a BN21K (or BN21L) cable between the BN21W-0B Y cable on each host bus adapter and the H8855-AA trilink on a BA356 storage shelf.

Figure 9–10 shows a two member TruCluster Server configuration using two BA356s for storage.

9–20Configurations Using External Termination or Radial Connections to Non-UltraSCSI Devices