NStor Technologies Disk Array Enclosure User Manual download pdf (Page 33)

Installation

General

Because of the enhancements in the CR8e, its possible to extend beyond the limits

set forth in the speciﬁcation. However, a symptom from exceeding this cable limit

is a SCSI bus lockup or “freeze.” If you experience a similar problem and are

aware of a cabling limit issue, reducing the length of cabling and returning the

total length to within the speciﬁed limit should resolve any problems.

If you have a cabling issue and require more information, contact nStor Technical

Support for further assistance. Data loss is possible under conditions of SCSI bus

lockup.

NOTE: Shielded data cables, such as those provided with the subsystem, must be

used to prevent radio frequency interference. It is recommended that you

use the cables provided by nStor. These cables have been tested and meet

stringent guidelines set forth by SCSI-3 ANSI speciﬁcations.

Termination

Termination is required at both ends of the SCSI bus. There are two sets of

jumpers on the I/O Interface card. One set of jumpers (JP1 and JP2) routes “Term

Power” in the event that the host controller is not providing it. The default setting

is the unjumpered condition (jumper offset on one pin only). The second set of

jumpers addresses a speciﬁc set of controllers that use the DEC Fault Bus

protocol. If your controller uses this protocol, you will need to jumper (jumper on

both pins) at location JP3 and JP4 on the backplane for the indicated channel that

will be used. A jumper at either of these locations will disable termination at that

point on the SCSI bus.

If you are using a controller that provides Term Power, no change is required and

SCSI bus termination will occur automatically.

Most RAID controllers provide termination for one end of the SCSI bus, while

the I/O Interface card provide ﬁnal termination at the other end of the bus.

Channel 0

Channel 1

JP3 and JP4

Fault Bus Protocol

Jumpers (Add to

disable termination)

JP1 and JP2

Channel 0 and 1

Term Power Jumpers

1 2 ... 28 29 30 31 32 33 34 35 36 37 38 ... 91 92

No comments

NStor Technologies Disk Array Enclosure User Manual Page 33