home *** CD-ROM | disk | FTP | other *** search
- Newsgroups: comp.unix.ultrix
- Path: sparky!uunet!ferkel.ucsb.edu!taco!gatech!swrinde!sdd.hp.com!cs.utexas.edu!sun-barr!ames!decwrl!pa.dec.com!granite.pa.dec.com!ajc
- From: ajc@pa.dec.com (AJ Casamento)
- Subject: Re: scsi disk for Decstations
- In-Reply-To: ccpaz@cc.uab.es's message of 6 Nov 92 15:09:06 +0200
- Message-ID: <AJC.92Nov10123927@thendara.pa.dec.com>
- Sender: news@PA.dec.com (News)
- Organization: Digital Equipment Corporation
- References: <1992Nov6.150906.70@cc.uab.es>
- Date: 10 Nov 92 12:39:27
- Lines: 65
-
-
-
-
- In article <1992Nov6.150906.70@cc.uab.es> ccpaz@cc.uab.es writes:
-
-
- >> Sorry for a too basic question.
- >> We want to add an external disk to our Decstation 5200, my question is
- >> do i have to limit my search inside digital or are there third party scsci
- >> disk suppliers compatible with Decstations?
- >> And how can i know the compatibility of the different vendor's disks with
- >> the machine?
- >> For example can i by an IBM scsci disk and plug it into a Decstation?
- >> I am looking for at least 2Gb , but for what i've seen i should by 2 disk of
- >> 1Gb each, does it exists a 2Gb or bigger external disk?
-
- >> M.Paz Alvarez
- >> Computer Center
- >> Universitat Autonoma Barcelona
- >> Bellaterra (Barcelona)
- >> Spain
-
- Senor Alvarez,
-
- Actually, it's not such a basic question. There are a number of problems that
- you can avoid by asking your disk drive vendor a couple simple questions:
-
- 1. Does the vendor have a SCSI-2 compliant firmware? (Or, does the vendor
- have a DEC firmware variant). There are some vendors who have disks that
- do not respond to a SCSI bus reset within 500 milliseconds and this can
- cause the disk drive not to be recognized.
-
- 2. Does the vendor's synchronous SCSI device allow for synchronous transfer
- to be negotiated (per the ANSI SCSI-2 specification) or is it hard-wired
- with a jumper? The DEC console firmware deals with the drive in asynch
- mode and will then attempt to negotiate synchronous when the OS boots.
-
-
- Also, if you intend to use a disk drive which formats to a larger than a 1.0GB
- size, you will need to be running Ultrix v4.2 or higher. If you are going to be
- looking at using SCSI based printers, scanners or communications hardware you
- may want to install the CAM SCSI subsets (they will become the default in the
- future).
-
- I've had a chance to see/work with disk drives from Seagate, Micropolis,
- Clearpoint, Maxtor and Hitachi. I've heard only good things about HP and IBM
- drives as well but I've not had any direct work contact with them. I've got no
- particular attachment to any of the above vendors (I'm not connected with them
- and I receive no money for my opinions) I'm just trying to answer your inquiry
- about disk drives.
-
- I hope that helps.
-
- Thanx,
- AJ
-
-
- **********************************************************************
- * AJ Casamento "The question is not whether or *
- * Digital's TRI/ADD Program not the opinions are mine; but *
- * 529 Bryant Ave. PAG-2 rather, which of my personalities *
- * Palo Alto, CA 94301-1616 do they belong to?" *
- * 415.617.3460 *
- * ajc@pa.dec.com *
- **********************************************************************
-