HP Serviceguard Under Cluster Configuration Parameters, Scsi Addressing in Cluster Configuration

	For more details of IPv6 address format, see the Appendix H
	(page 378).
NETWORK_FAILURE_DETECTION	When there is a primary and a standby network card,
	Serviceguard needs to determine when a card has failed,
	so it knows whether to fail traffic over to the other card. The
	configuration file specifies one of two ways to decide when
	the network interface card has failed:
	•	INOUT
	• INONLY_OR_INOUT
	The default is INOUT.
	See “Monitoring LAN Interfaces and Detecting Failure: Link
	Level” (page 69) for more information.
NETWORK_AUTO_FAILBACK	See the NETWORK_AUTO_FAILBACK parameter description
	under“Cluster Configuration Parameters ” (page 109).
Kind of LAN Traffic	Identify the purpose of the subnet. Valid types include the
	following:
	•	Heartbeat
	•	Client Traffic
	•	Standby

This information is used in creating the subnet groupings and identifying the IP addresses used in the cluster and package configuration files.

Setting SCSI Addresses for the Largest Expected Cluster Size

SCSI standards define priority according to SCSI address. To prevent controller starvation on the SPU, the SCSI interface cards must be configured at the highest priorities. Therefore, when configuring a highly available cluster, you should give nodes the highest priority SCSI addresses, and give disks addresses of lesser priority.

For SCSI, high priority starts at seven, goes down to zero, and then goes from 15 to eight. Therefore, seven is the highest priority and eight is the lowest priority. For example, if there will be a maximum of four nodes in the cluster, and all four systems will share a string of disks, then the SCSI address must be uniquely set on the interface cards in all four systems, and must be high priority addresses. So the addressing for the systems and disks would be as follows:

Table 6 SCSI Addressing in Cluster Configuration

System or Disk	Host Interface SCSI Address
Primary System A	7
Primary System B	6
Primary System C	5
Primary System D	4
Disk #1	3
Disk #2	2
Disk #3	1
Disk #4	0
Disk #5	15

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