SCSI Drives Not Detecting Properly

FlintstoneFlintstone SE Florida
edited July 2003 in Hardware
I've got an ALR 3 drive sca drive cage. I also have 2-15K 18.2 Gig wide ultra 3 (U160) Compaq branded Cheetahs and 1-15K 18.2 Gig U160 Seagate branded Cheetah. The Seagate drive is detected as a U160 drive but the 2 Compaq branded drives are only detected as scsi2. All in the same cage at the same time , no matter the location in the cage. They post as U160 with an sca to 68 pin converter but not in the ALR cage. Any Ideas?

Thanks,

Flint:cool:

Comments

  • citrixmetacitrixmeta Montreal, Quebec Icrontian
    edited June 2003
    can u please the model # of the compaq drive,
  • AgeekAgeek
    edited June 2003
    So-- with both Compaq private-labelled ones in the ALR both detect as U160s when the non-private labelled on is absent??? Are there any channel or ID jumpers or dips on them, and if so is there a conflict so any two drives are set in conflict with each ohter or with the controller in the cage??? In SCSI, usually the controller takes one ID for itself. Conflict that with a drive, the whole channel can go awry or stagger to a very slow rate of output. Try one drive on each channel if this is a multichannel card in cage. If one conflicts one will go slower or invalid where a conflict exists. Yes, I know the word channel is not perfectly right for SCSI per se, but practically SCSI has two or more channels and each channel can handle 7 or more devices-- higher the SCSI typing the higher the number of devices per physical channel are allowed.

    You can also conceivably run into this issue with a SCA adapter for a SCSI-II UW stuck onto a SCSI-III drive as the adapter tends to internally buffer some and the RAM used for that is usually speced for speed the adapter is rated for-- this last situation I have not managed to create, but had a friend do just exactly this once.

    John Danielson.
  • FlintstoneFlintstone SE Florida
    edited June 2003
    Compaq drive model # BF01864663
    Drive CPN: 235065-001
    Factory Part No.:ST4006-023 (matches Seagate part no ST4006-001)
    and says:18.2-GB 15000RPM
    Wide Ultra3 SCSI

    In terms of the cage:
    It is on a single connector on a 7 connecteor terminated twisted scsi cable and has 3 sca connectors on a single pcb to one 68 pin connector. The cage is connected to an LSI Megaraid 1600 Elite dual channel raid controller on channel 2. the drives show id's in the megaraid setup utility of 4,5, and 6 and change if I move the drives around, which I take to mean the ID's are assigned by the cage pcb. The scsi2 or scsi3 detection follows the drives, not the connectors on the backplane. There are only 3 drives on the channel, and 4 drives on channel 1. The drives on channel 1 show SCSI3, all have either 68 pin native interface or an adapter. If you can think of anything else, please holler!
    Oh yea, the Compaq branded drives NEVER show as scsi3 in the ALR cage, but do on separate adapters.

    Thanks,
    Flint
  • FlintstoneFlintstone SE Florida
    edited June 2003
    Here's a scan of the drives in question.
  • COGeekCOGeek Colorado Springs, CO
    edited July 2003
    This is just a guess, but you could be running into a problem where the Compaq drives don't like the backplane you're putting them in, so they negotiate for a lower speed.

    there could be a few reasons for this, signal integrity problems, etc. Is there a SAF-TE device in the cage you are putting them in?

    On thing that will usually solve problems like this is checking if there are firmware updates for the hard drives, SAF-TE devices, and the SCSI controller itself. Most likely there are newer versions if they haven't been updated since they were purchased. The firmware for the SCSI controller should be pretty easy to find, but it's not so easy for hard drives and SAF-TE devices.
  • FlintstoneFlintstone SE Florida
    edited July 2003
    Please induldge me and tell me what a SAF-TE device is! I have no idea if there is one or not or even what to look for.

    Thanks,
    Flint
  • COGeekCOGeek Colorado Springs, CO
    edited July 2003
    Well, SAF-TE stands for SCSI Accessed Fault Tolerant Enclosure. Most, but not all, of the backplanes I have worked with have one of these chips in them. You can tell if there is one because it will show up during the bus scan like any other target device. I think in Windows it shows up as a backplane processor or something like that.

    These chips are usually used for monitoring the operating environment of the backplane; controlling the various LED's and reporting temperature or power problems, etc.
  • AgeekAgeek
    edited July 2003
    To have a chance of helping more I would need the backplane model number. Most SCA drives can be made two ways-- for standalone (not used with bckplanes) and OEM. OEMs can be set up for exactly one mfr's backplanes and then coded so that the backplane provides the drive ID. In a different backplane than what they were mfr'd for the drive ID may never get set right-- but a default might work if only drive on cable.

    If standalone as only drive on cable almost any SCA should work, but with another drive they might not have a valid ID unless on exactly the backplane they were made to go with. Soem SCAs are like SCSIs, and one on chain needs to be last in line and terminated. Some adapters terminate and some not. Some are jumpered and can be set to not terminate. Only one drive should be terminated.

    Some backplanes have one socket that is a terminated socket, this socket always is last socket in use. I have seen SCSI devices that have backplanes where the termination is pre-socket, these are not nice as you end up using one less drive than the number of sockets.

    John Danielson.
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