From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from minnie.tuhs.org (minnie.tuhs.org [45.79.103.53]) by inbox.vuxu.org (OpenSMTPD) with ESMTP id 5410f75e for ; Mon, 25 Nov 2019 17:40:50 +0000 (UTC) Received: by minnie.tuhs.org (Postfix, from userid 112) id 60AFA9C604; Tue, 26 Nov 2019 03:40:49 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 03FEA93D74; Tue, 26 Nov 2019 03:40:29 +1000 (AEST) Authentication-Results: minnie.tuhs.org; dkim=pass (1024-bit key; unprotected) header.d=kilonet.net header.i=@kilonet.net header.b="mm4Ezc4+"; dkim-atps=neutral Received: by minnie.tuhs.org (Postfix, from userid 112) id C9CDB93D74; Tue, 26 Nov 2019 03:40:27 +1000 (AEST) Received: from p3plsmtpa08-10.prod.phx3.secureserver.net (p3plsmtpa08-10.prod.phx3.secureserver.net [173.201.193.111]) by minnie.tuhs.org (Postfix) with ESMTPS id 43BE093D71 for ; Tue, 26 Nov 2019 03:40:27 +1000 (AEST) Received: from medusa.kilonet.net ([72.69.223.115]) by :SMTPAUTH: with ESMTPA id ZILaigcuR4R98ZILainfoS; Mon, 25 Nov 2019 10:40:26 -0700 Received: from [199.89.231.101] (ender.kilonet.net [199.89.231.101]) by medusa.kilonet.net (8.14.8/8.15.1) with ESMTP id xAPHePdw016404 for ; Mon, 25 Nov 2019 12:40:25 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kilonet.net; s=default; t=1574703625; bh=6GC2uttPhzWShsa0UPjWBMXU/0QlFxy09L2uphhpAVM=; h=Subject:To:References:From:Date:In-Reply-To; b=mm4Ezc4+Dk7ms6bHUeIMQjv30J0wEK5P+bqIfASpnIIfj26oAlXgSGMHZhsr4RFP+ F+O94tXY7PRXMY8r0EkX2oG33/1GFevxHeI9KhCGcq7pEaoEbzLaBTgWGYSjHIYPgL /w28+DJCg0GgMJfUH6OG7iiQ9XKrxXY22Qwt7WpQ= To: tuhs@minnie.tuhs.org References: <20191124225239.GG18200@mcvoy.com> <20191125032404.GM18200@mcvoy.com> <0a6fb097-fe79-1633-0205-1c45f0a56953@bitsavers.org> From: Arthur Krewat Message-ID: <96b55e5e-4b05-f7b7-c2ae-efdae7c18b2f@kilonet.net> Date: Mon, 25 Nov 2019 12:40:22 -0500 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.9.1 MIME-Version: 1.0 In-Reply-To: <0a6fb097-fe79-1633-0205-1c45f0a56953@bitsavers.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-CMAE-Envelope: MS4wfMTasp8G7639AAgeAugxyJN9LDik4x1lM1aqYsRQWw94SVDjSOvQMrGQKRHJP5jx5646YCQc+gBdybkRC5Nq0uMpEDoDokjlFsQ3LTboH7c1OPvdxWvK 5Oz2qDwSYC2AKfab1U+ThcswW1urYVdI9wgMy6KU7fHB/VDNNIEuHSwhdhueFYep7ztEkvWabhO0IQ== Subject: Re: [TUHS] Someone wants to use an exabyte X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" A few years back, I decided to go through my stack of 8mm Exabyte-written tapes... An early Exabyte 8200 2GB Exabyte drive was useless. A 2/5G drive worked. There were errors on one or two tapes. But each and every one was an analog 8mm video tape, not a real data tape. And I was able to splice the backup set enough so that whatever it was written with would be happy enough to restore the data once pieced back together. A mix of tar, and ufsbackup for the most part. During this process, I bought an Exabyte Mammoth off eBay - didn't use it much, but it read those old tapes just fine. I was able to recover scads of personal stuff that I already had copies of, along with a few dumps of the USENET systems I was using to serve as a 3-modem BBS for USENET. And yes, sometimes, I go back into old backup tapes to recover data I already have on disk. I hate bit-rot, I do whatever I can to mitigate it. art k. PS: DAT 4mm tape drives, especially whatever Sun was using, were awful. Around 50% of them I dealt with all got into a mode within the first year where they would accept a tape, and just kick it back out right away. Because they were under support, they were just replaced, so I never looked into it hardware-wise. On 11/25/2019 12:07 PM, Al Kossow wrote: > > On 11/24/19 7:24 PM, Larry McVoy wrote: >> So that sounds like a different problem. People correct me if I'm >> wrong but the exabyte drives seemed to have a head alignment problem. > They are 8mm helical-head drives. they wouldn't go out of alignment by > bumping them, the worse would be the tape would lose tension if you > smacked the tensioning arms hard enough > > They do have a lot of rubber parts inside. > Rollers crack and belts go soft. I have several dozen dead EX8200s from that. > > I have a whole box of 8mm backup tapes that just came in, and a small > number of working drives. The Linux software I wrote to do 9 track tape recovery > from a SCSI 9 track drive works just fine on an Exabyte. > > And I'm not offering to read Jason's mystery reels. > > > > > >