From owner-freebsd-hackers Wed Sep 30 13:04:49 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id NAA11305 for freebsd-hackers-outgoing; Wed, 30 Sep 1998 13:04:49 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from uni4nn.gn.iaf.nl (osmium.gn.iaf.nl [193.67.144.12]) by hub.freebsd.org (8.8.8/8.8.8) with SMTP id NAA11277 for ; Wed, 30 Sep 1998 13:04:39 -0700 (PDT) (envelope-from wilko@yedi.iaf.nl) Received: by uni4nn.gn.iaf.nl with UUCP id AA11903 (5.67b/IDA-1.5); Wed, 30 Sep 1998 21:29:28 +0200 Received: (from wilko@localhost) by yedi.iaf.nl (8.8.8/8.6.12) id UAA01817; Wed, 30 Sep 1998 20:46:43 +0200 (CEST) From: Wilko Bulte Message-Id: <199809301846.UAA01817@yedi.iaf.nl> Subject: Re: Exabyte 8500 in low density (2GB) mode... How? In-Reply-To: <19980929223911.A2555@Denninger.Net> from Karl Denninger at "Sep 29, 98 10:39:11 pm" To: karl@denninger.net (Karl Denninger) Date: Wed, 30 Sep 1998 20:46:43 +0200 (CEST) Cc: stox@enteract.com, hackers@FreeBSD.ORG X-Organisation: Private FreeBSD site - Arnhem, The Netherlands X-Pgp-Info: PGP public key at 'finger wilko@freefall.freebsd.org' X-Mailer: ELM [version 2.4ME+ PL38 (25)] Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG As Karl Denninger wrote... > On Tue, Sep 29, 1998 at 10:08:51PM -0500, Kenneth P. Stox wrote: > > > > On Tue, 29 Sep 1998, Karl Denninger wrote: > > > > > I don't believe an 8500 CAN write 8200 format. > > > > > > It can READ 8200 format, but not write it. There are differences in track > > > density and head gap size, and as such I don't believe this is even > > > physically possible. > > > > An 8500 can write in 8200 density just fine. Reliably reading that tape on > > an 8200 is another question entirely. The 8500 writes a far narrower track > > than the 8200. Reliability with Exabytes in it's own right is enough stuff for a Phd thesis anyway ;-) > > Although this represents a challenge, it is not impossible. If the tape > > has never been used on an 8200, and then written on the 8500, chances are > > it will work. However, if the tape had previously been written on an 8200, > > the 8500 will never completely erase the data left in the wider tracks by > > the 8200. When this tape is then written on the 8500 ( in 8200 density ) > > and mounted on an 8200, the 8200 can become confused by the "old" data > > left on the outside of the narrower tracks. > > > > -Ken Stox > > stox@enteract.com > > stox@fnal.gov > > In other words: > > Bulk erase the tape, write it, and then immediately read it on the 8200. > > That's what I thought. Interchange was a problem. Residual data 'just outside' the 8500 trackwidth can indeed be a problem. Although I myself had reasonable good luck with 8200 (at home) and 8505 (at work) interchanges. Wilko _ ______________________________________________________________________ | / o / / _ Bulte email: wilko@yedi.iaf.nl |/|/ / / /( (_) Arnhem, The Netherlands WWW : http://www.tcja.nl ______________________________________________ Powered by FreeBSD __________ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message