From owner-freebsd-hackers@FreeBSD.ORG Fri May 17 00:31:02 2013 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id B379B909 for ; Fri, 17 May 2013 00:31:02 +0000 (UTC) (envelope-from grog@lemis.com) Received: from w3.lemis.com (w3.lemis.com [208.86.224.149]) by mx1.freebsd.org (Postfix) with ESMTP id 8E6AA8DA for ; Fri, 17 May 2013 00:31:02 +0000 (UTC) Received: from eureka.lemis.com (1032.x.rootbsd.net [208.86.224.149]) by w3.lemis.com (Postfix) with ESMTP id A87743B736; Fri, 17 May 2013 00:31:00 +0000 (UTC) Received: by eureka.lemis.com (Postfix, from userid 1004) id 08ABAF75F3; Fri, 17 May 2013 10:30:59 +1000 (EST) Date: Fri, 17 May 2013 10:30:59 +1000 From: Greg 'groggy' Lehey To: Zaphod Beeblebrox Subject: Re: tape (sa0) on sparc64 ? Message-ID: <20130517003058.GW77641@eureka.lemis.com> References: <0D672BB1-1928-4F7A-BF72-CA7EE15D0563@gid.co.uk> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="Tln/wzp9jsNjmSUr" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.3i Organization: The FreeBSD Project Phone: +61-3-5346-1370 Mobile: +61-418-838-708 WWW-Home-Page: http://www.FreeBSD.org/ X-PGP-Fingerprint: 9A1B 8202 BCCE B846 F92F 09AC 22E6 F290 507A 4223 Cc: FreeBSD Hackers X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 17 May 2013 00:31:02 -0000 --Tln/wzp9jsNjmSUr Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Thursday, 16 May 2013 at 19:56:14 -0400, Zaphod Beeblebrox wrote: > On Thu, May 16, 2013 at 5:08 PM, Bob Bishop wrote: >> On 16 May 2013, at 21:51, Zaphod Beeblebrox wrote: >> >>> I have to retrieve some very old backups. They were made on FreeBSD and >>> are on tape... specifically DDS4. [etc] >>> However, attached to either controller (after a reboot of the machine >> and a >>> powercycle of the drive), I get: >>> >>> [1:25:325]root@run:/home/foo> dd if=/dev/sa0 of=tape5 >>> dd: /dev/sa0: Input/output error >>> 0+0 records in >>> 0+0 records out >>> 0 bytes transferred in 0.002930 secs (0 bytes/sec) >>> >>> ... which is a return code of '1' and no messages on the console... >>> >>> I have, before you ask, tried "bs=10k" and 20k ... but I believe this >>> command should run by itself fetching the first 512 bytes of each block >> --- >>> narrowing down the block size logically comes after making the tape go. >> >> >> Try bs=64k > > Same result. Besides, as far as I understand, the proper operation > (if the blocksize is too small) is to read the first $n bytes and > then write them to the output.. The obvious question: can you write tapes and read them back? My experience with DDS tapes was of extreme unreliability. The age doesn't make things any easier. Greg -- Sent from my desktop computer. Finger grog@FreeBSD.org for PGP public key. See complete headers for address and phone numbers. This message is digitally signed. If your Microsoft MUA reports problems, please read http://tinyurl.com/broken-mua --Tln/wzp9jsNjmSUr Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (FreeBSD) iEYEARECAAYFAlGVekIACgkQIubykFB6QiNbnwCfes0z89YVMRVVQEnUe0NzH+w0 uAIAn3XRJaVEt2+55iM7vzRYWNTUmPa2 =IEct -----END PGP SIGNATURE----- --Tln/wzp9jsNjmSUr--