From owner-freebsd-questions Thu Sep 9 6:55:21 1999 Delivered-To: freebsd-questions@freebsd.org Received: from caladan.tdx.co.uk (caladan.tdx.co.uk [195.188.177.4]) by hub.freebsd.org (Postfix) with ESMTP id C0C9214D4C for ; Thu, 9 Sep 1999 06:53:37 -0700 (PDT) (envelope-from kpielorz@tdx.co.uk) Received: from tdx.co.uk (lorca-tx.tdx.co.uk [195.188.177.242]) by caladan.tdx.co.uk (8.9.3/8.9.3/Kp) with ESMTP id OAA57096; Thu, 9 Sep 1999 14:54:38 +0100 (BST) Message-ID: <37D7BBAD.EB2385A7@tdx.co.uk> Date: Thu, 09 Sep 1999 14:52:45 +0100 From: Karl Pielorz Organization: TDX - The Digital eXchange X-Mailer: Mozilla 4.61 [en] (WinNT; I) X-Accept-Language: en MIME-Version: 1.0 To: Ian Diddams Cc: freebsd-questions@FreeBSD.ORG Subject: Re: Backups (yet again I hear you sigh) References: <37D50936.45C520F8@freenet.uk.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Ian Diddams wrote: > So - my query is merely this - what the proverbial am I doing > incorrectly ('cos I must be missing something very fundamental) and how > do I force the compression on the backup ? The DAT should ship with compression 'on' by default, unless you change the DIP switches, ours did here... Have you tried using the '-a' option with Dump?, ie. " -a ``auto-size''. Bypass all tape length considerations, and enforce writing until an end-of-media indication is returned. This fits best for most modern tape drives. Use of this option is particu- larly recommended when appending to an existing tape, or using a tape drive with hardware compression (where you can never be sure about the compression ratio). " I have a SureStore 24e plugged into my -current box at the moment (I must have missed your orignial postings), looking at the output of df - my nightly backups are now around 18gb's admitadly done as 5 seperate 'chunks' of between .2 and 9gb's (using the non-rewinding device), but they all go on the tape fine... (This also assumes as you say that Solaris ufsdump is akin to BSD dump). Also, is the tape is rewound before you start? (i.e. mt rewind) - I've fallen foul of that one before... :) -Karl To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message