From owner-freebsd-questions Mon Nov 12 18:26:29 2001 Delivered-To: freebsd-questions@freebsd.org Received: from grumpy.dyndns.org (user-24-214-92-93.knology.net [24.214.92.93]) by hub.freebsd.org (Postfix) with ESMTP id D753937B405 for ; Mon, 12 Nov 2001 18:26:25 -0800 (PST) Received: from localhost (localhost [127.0.0.1]) by grumpy.dyndns.org (8.11.6/8.11.6) with ESMTP id fAD2PDU67256; Mon, 12 Nov 2001 20:25:13 -0600 (CST) (envelope-from dkelly@grumpy.dyndns.org) Message-Id: <200111130225.fAD2PDU67256@grumpy.dyndns.org> X-Mailer: exmh version 2.5 07/13/2001 with nmh-1.0.4 To: Bill Moran Cc: "Stephen Hilton" , "FreeBSD Questions" From: David Kelly Subject: Re: reading SGI backup tapes on FreeBSD In-reply-to: Message from Bill Moran of "Mon, 12 Nov 2001 20:47:56 EST." <01111220475600.01499@proxy.the-i-pa.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Mon, 12 Nov 2001 20:25:13 -0600 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Bill Moran writes: > On Monday 12 November 2001 16:10, Stephen Hilton wrote: > > Bill, > > > > > According to the SGI backup/restore program, cpio was used to make the > > > backups. So I've tried cpio on FreeBSD with no success. Usually I get > > > an "Input/Output" error. > > > > "bru" is used also on these system for backup, IIRC your error message > > sound familiar to trying to read a SGI bru DAT tape on a FreeBSD system > > with tar. > > Hmmm ... would be something to try, except I can't even use dd. I wanted to > try using the options in dd to switch the byte-order, but dd won't even let m e > read the tape. (complains of "input/ouput error") > At this point I'm guessing that the tape will only work on the DAT drive that > wrote it, if at all. Maybe the thing was proprietary in some way, or so far out > of alignment that the tapes are unreadable by anything else. Or maybe the > tapes were just mishandled during storage and are no longer any good (they're > three+ years old) Am tuning in late but has anybody mentioned SGI's Irix liked to write DAT tapes with a 256k blocksize? Also was bad about remembering the last blocksize used if one doesn't specify so if you had a harebrained user last use the tape drive who thought 1MB blocksize wrote faster and used less tape then your tape will be the same. Last time I tried FreeBSD couldn't handle more than 64k blocksize via SCSI. Have noticed the ata device will sometimes peg the max resolution in "systat -v" so the 64k limit isn't inherent in the kernel. Some have suggested that it could be raised at kernel compile time but not all SCSI cards could handle it and the code to handle the exceptions didn't exist. Mention this as a starting point as I'm about 3 years beyond following this issue closely. Say about FreeBSD 3.0. -- David Kelly N4HHE, dkelly@hiwaay.net ===================================================================== The human mind ordinarily operates at only ten percent of its capacity -- the rest is overhead for the operating system. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message