Compaq AA-RHGWC-TE - Manual (Page 34)

UNIX Version 5.0, 16 devices are supported on a SCSI bus. Therefore,
multiple BA356 storage units can be used on the same SCSI bus to allow
more devices on the same bus.
Figure 1–4 shows the configuration in Figure 1–3 with a second UltraSCSI
BA356 storage unit that provides an additional seven disks for highly
available applications.
Figure 1–4: Two-Node Cluster with Two UltraSCSI DS-BA356 Storage Units
ID 8
ID 9
ID 10
ID 11
ID 12
ID 13
PWR
ID 5
PWR
Shared
SCSI
Bus
Clusterwide
/, /usr, /var
Member 1
Boot Disk
Member 2
Boot Disk
Quorum
Disk
UltraSCSI
BA356
ID 4
ID 14 or
redundant
power
supply
Host Bus Adapter (ID 7)
Network
Memory
Channel
Interface
Memory Channel
Host Bus Adapter (ID 6)
Memory Channel
Member
System
2 Member
System
1
Tru64
UNIX
Disk
ID 5
ID 4
ID 6
ID 3
ID 2
ID 1
ID 0
Data
disks
Do not use for
data disk. May
be used for
redundant power
supply.
Data
Disks
UltraSCSI
BA356
ZK-1590U-AI
This configuration, while providing more storage, has a single SCSI bus that
presents a single point of failure. Providing a second SCSI bus would allow
the use of the Logical Storage Manager (LSM) to mirror the /usr and /var
1–10 Introduction