SCSI Hard Drive Testing
PREREQUISITE =
This document assumes you are familiar with how Free Geek tests/wipes IDE & SATA HDs.
First triage the drives here SCSI Hard Drive Triage
Overview of the test station
We have an external enclosure for testing up to 12 "80-pin" HDs (connector shaped like a hollow "D"). Also, we have an internal cable, & power supply extender, with room for up to 4 "68-pin" HDs (also "D" shaped, but with pins).
NOTE: Our current test script has trouble displaying the in-progress detail for more than 5 or 6 HDs, so, even tho' we could test up to 16 HDs on this test station, doing only 5 or 6 is easier to manage. Also, testing more than 5 or 6 72GB drives can take 20+ hours to finish, so it's really more efficient to keep the batch-size down.
Jumpers
There are usually no jumpers on the 80-pin HDs that go into the external enclosure, the enclosure jumpers them. If there are any, remove them all. As for 68-pin HDs, where IDE HDs are jumpered "Master" or "Slave", SCSI HDs are jumpered numerically "0" thru "15". There will be diagrams on the HDs, which is good, because the patterns run from left to right OR right to left (just like with IDE HDs).
Drive ID Jumpers
There will be 4 jumpers, labeled "0 1 2 3" or "1 2 3 4" or "1 2 4 8". Jumpering a combination of these will give IDs of 0 thru 15. Think of the "1 2 4 8" pattern: no jumpers gives 0, all 4 jumpered gives 15 (1 + 2 + 4 + 8), jumpers on 1 & 2 gives 3, jumpers on 1 & 4 gives 5, jumpers on only 1 of the 4 gives 1 or 2 or 4 or 8. IMPORTANT NOTE = do NOT jumper an HD to 6 or 7, these are used by the controller cards (some cards use 6, others use 7). If you do, the drive will not show up, giving you a false negative.
Other
68-pin SCSI HDs often have a 2nd set of jumpers. These are not for ID numbers, but rather for settings like termination, spin delay, & other SCSI-specific & esoteric things we usually do not care about. REMOVE all jumpers from this pin array. Then, read the pin diagram, looking for "Motor Enable", or a similar phrase. Usually the drive will "spin up" & be recognized without this jumper, but if not, try adding a jumper here.
Test Station Repair & Maintenance
This will become a full discussion of hardware inventory for a SCSI HD test station. Mostly this will matter when an internal cable wears out.
Cables
Do not connect the internal & external cables to the same controller card, as this creates the risk of having 1 of 2 drives be invisible because they are jumpered to the same ID on the same channel. It can be done, but it's tricky because there is no standardization RE which connectors are on which channel. Basically, when swapping cables, plug the new cable into the same connector the old one was on.