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- Newsgroups: comp.sys.mac.hardware
- Path: sparky!uunet!mcsun!sunic!aun.uninett.no!ugle.unit.no!news
- From: Arne.Venstad@delab.sintef.no
- Subject: Strange HD behaviour
- Message-ID: <1992Aug17.105710*Arne.Venstad@delab.sintef.no>
- Sender: news@ugle.unit.no (NetNews Administrator)
- Organization: SINTEF DELAB, Trondheim, Norway.
- Date: 17 Aug 92 10:57:10
- Lines: 59
-
- First a question which might have general interest:
- I have hooked up several different external hard drives to my Mac si and
- observed that some of the drives prevent the Mac from booting unless
- they are powered up. Other drives can be connected to the SCSI bus, but not
- powered up and the Mac will boot happily. In all cases there is only one SCSI
- device connected in addition to the internal drive in the si.
- Is this a termination problem? (The drives that prevent booting when unpowered,
- do not show the same effect when connected to Plus'es or Mac II's).
-
- My second problem is for the specially interested:
- Our SUN lab recently trashed an external 600 MB CDC drive because it was "rotten".
- I took the drive home, re-plugged it, and hooked it to my Mac si 17/105. After a
- couple of failures I was able to format the drive using both Disk Manager Mac and
- Alliance Power Tools. I then ran the test suite in Alliance Power Tools. It worked
- ok until it came to the SCSI Verify test and Hardware exercise test. Then it reported
- bad sectors (sense code conditions). Perhaps not surprising since the drive was
- already classified as "rotten".
- However, what interested me was that when the trouble started, the drive seemed to
- spin irregularly and even halt completely. This happened several times during testing,
- but not always at the same place. The trouble seemed to be intiated by some of the
- special SCSI commands of the test suite.
- I have also copied lots of program and data to the drive, run several applications
- off the drive for several hours, copied over hundred MB of data to and from it
- without any trouble and without a single corrupted byte.
-
- I now wonder if somebody from the above description get any idea of what is wrong
- with this drive?
-
- The following information is an extract from the test suite report:
-
- Device reported Vendor ID: 'CDC'
- Device reported Product ID: '94181-15'
- Device reported Firmware: '5860'
-
- SCSI id: 1 Reported size: 573 MB
-
- ...
-
- Average Sequential Seek Time: 2.05 ms
- Average Butterfly Seek Time: 17.43 ms
- Average Pattern Seek Time: 9.15 ms
- Outer To Inner Rings Seek Time (not performed)
-
- There were 41 defects reported by the devices' P-list. This is most certainly normal.
- There were 0 defects reported by the devices' G-list. This is most certain normal.
- The SCSI Verify test discovered 42 bad sectors (sense code conditions)
- The Media Analysis test reported 0 sense code conditions.
- <<In another test run problems were reported also here!>>
- The Hardware Exercise test reported 59 sense code conditions and concluded
- that the device has problems reading the media.
-
- ...
-
- Thank you for any information!
-
- Arne Venstad E-mail: Arne.Venstad@delab.sintef.no
- SINTEF DELAB
- N-7034 Trondheim,
- Norway.
-