Compaq AA-RHGWB-TE manual 10Introduction

this slot can be used for a second power supply to provide fully redundant power to the storage shelf.

Note that 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 as 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 5.0A 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.

1.6.2Two-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 UNIX Version 5.0, 16 devices are supported on a SCSI bus. Therefore,

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