Silicon Graphics CHALLENGE CMN A012B, Owner'S Manual

Page: 35 / 40

27
Appendix B
B. Software Guidelines
This chapter provides software guidelines to operate the Vault and
SCSIBox 2. This upgrade requires IRIX 5.0 or later.
Disk Striping
Disk striping increases workstation throughput by distributing file data
across multiple disk drives through logical volumes. For detailed software
descriptions of how hard drives are configured to support disk striping, see
the “Logical Volumes” subsection in the
IRIX Advanced Site and Server
Administration Guide .
Caution: Systems utilizing disk striping must have a well-tested and
maintained backup plan. If a single disk drive failure occurs, the entire file
structure can be affected because sections of the filesystem are distributed
among different disk drives.
New Addressing Scheme for Drives
An IO4 board can have up to eight SCSI bus interfaces (or channels). See
Figure B-1. Compare this with the IO3, the predecessor to the IO4, which has
only two channels (or SCSI bus interfaces). In addition, the new, wider
68-pin SCSI connector on the chassis now enables connectivity with up to 15
devices per channel.
Due to this expanded connectivity, the IRIX and PROM monitor drive
addressing scheme has been modified to accommodate the increased
number of drives and channels.