Compaq AA-RHGWC-TE - Manual (Page 33)

this slot can be used for a second power supply to provide fully
redundant power to the storage shelf.
With the use of the cluster file system (see the TruCluster Server Cluster
Administration manual for a discussion of the cluster file system), the
clusterwide root (/), /usr, and /var file systems could be physically placed
on a private bus of either of the member systems. But, if that member
system was not available, the other member system(s) would not have access
to the clusterwide file systems. Therefore, placing the clusterwide root (/),
/usr
, and /var file systems on a private bus is not recommended.
Likewise, the quorum disk could be placed on the local bus of either of the
member systems. If that member was not available, quorum could never be
reached in a two-node cluster. Placing the quorum disk on the local bus of
a member system is not recommended because it creates a single point of
failure.
The individual member boot and swap partitions could also be placed on
a local bus of either of the member systems. If the boot disk for member
system 1 was on a SCSI bus internal to member 1, and the system was
unavailable due to a boot disk problem, other systems in the cluster could
not access the disk for possible repair. If the member system boot disks are
on a shared SCSI bus, they can be accessed by other systems on the shared
SCSI bus for possible repair.
By placing the swap partition on a system’s internal SCSI bus, you reduce
total traffic on the shared SCSI bus by an amount equal to the system’s
swap volume.
TruCluster Server Version 5.1 configurations require one or more disks to
hold the Tru64 UNIX operating system. The disk(s) are either private disk(s)
on the system that will become the first cluster member, or disk(s) on a
shared bus that the system can access.
We recommend that you place the /usr, /var, member boot disks, and
quorum disk on a shared SCSI bus connected to all member systems. After
installation, you have the option to reconfigure swap and can place the swap
disks on an internal SCSI bus to increase performance. See the TruCluster
Server Cluster Administration manual for more information.
1.5.2 Two-Node Clusters Using UltraSCSI BA356 Storage Units with
Increased Disk Configurations
The configuration shown in Figure 1–3 is a minimal configuration, with a
lack of disk space for highly available applications. Starting with Tru64
Introduction 1–9