Compaq ProLiant Cluster HA/F500 Administrator Guide

Setting Up the ProLiant Cluster HA/F500 with Hubs
2-32 ProLiant Cluster HA/F500 for MA8000 Administrator Guide
COMPAQ CONFIDENTIAL
Writer: Woody Jernigan File Name: c-ch2
Codename: Chargers Part Number: 355220-006 Last Saved On: 7/26/02 2:48 PM
ALPA Assignment
All HA/F500 configurations require a LOOP_HARD topology. Changing the port
topology to LOOP_HARD requires an ALPA for the controller port. The ALPA is
used to identify the device on the arbitrated loop whenever the loop initialization
process (LIP) occurs. Having an ALPA value assigned increases the likelihood that
the value will be available for that device when the LIP occurs. If a value is not
chosen or is not available, the initialization process searches through the entire table
of acceptable ALPA values until it finds a value that is available for use by the
device.
Server-to-Storage Connection Paths
Server-to-storage connection paths must be defined when configuring multiple
cluster configurations for multibus failover. If connections are not defined, all new
connections (the automatically generated “!NEWCONXX” connections) will be
assigned Unit Offset 0, and the cluster using port 2 of each controller will not be able
to access the logical units intended for its use. The connection path setting helps
segregate the logical units between the two clusters.
NOTE: The XX in !NEWCONXX refers to the connection number.
Assigning server-to-storage connection paths is necessary only in the multibus
failover configuration (Figure 2-6).