Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!crdgw1!uunet!talgras!david
From: david@talgras.UUCP (David Hoopes)
Newsgroups: comp.unix.admin
Subject: Re: Unhooking scsi devices while machine is running
Message-ID: <77@talgras.UUCP>
Date: 27 May 91 15:17:44 GMT
References: <1991May24.143831.10687@csl.dl.nec.com>
Reply-To: david@talgras.UUCP (David Hoopes)
Distribution: usa
Organization: Tallgrass Technologies Inc.
Lines: 32

In article <1991May24.143831.10687@csl.dl.nec.com> harrison@csl.dl.nec.com (Mark Harrison) writes:
>We have a portable scsi qic-150 tape drive that we share among
> [stuff deleted]
>My questions:
>
>1.  Is there *any* significance to the order of daisy chaining?
>
yes and no.  No, the order of devices dosn't matter.  Yes, the terminator
must be at the end of the chain.  Some devices have internal terminators. 
If one of the devices you have has an internal terminator then it must be
the last device in the chain.

>2.  Is it safe to plug and unplug the tape drive while the system
>    is up?
We do this all the time around here (we develope for scsi products).  We
manage to blow up host adapters on a fairly regular basis.  All we have to
do is walk to the other end of the building and have them repaired so we
don't worry about it to much.

>
>3.  (this is the point of the whole posting)  Will I screw things
>    up if I simply plug and unplug the tape drive into the disk
>    drive while the system is running?
Yes!  You would probably get away with it for awhile but sooner or later
something would die.


-- 
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David Hoopes                              Tallgrass Technologies Inc. 
uunet!talgras!david                       11100 W 82nd St.          
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