Managing Serviceguard 12th Edition, March 2006

Understanding Serviceguard Hardware Configurations
Redundant Disk Storage
Chapter 250
Figure 2-7 Cluster with Fibre Channel Switched Disk Array
This type of configuration also uses PV links or other multipath software
such as VERITAS Dynamic Multipath (DMP) or EMC PowerPath.
Root Disk Limitations on Shared SCSI Buses
The IODC firmware does not support two or more nodes booting from the
same SCSI bus at the same time. For this reason, it is important not to
attach more than one root disk per cluster to a single SCSI bus.
For example, Figure 2-8 shows a supported configuration in which two
nodes share an external SCSI bus and Node A has its primary root disk
connected to the bus, but node B has its primary root disk connected to a
different bus. (Numbers 0 to 3, 6 and 7 are SCSI addresses on the
different buses.)