From owner-freebsd-questions Fri May 31 8:48:22 2002 Delivered-To: freebsd-questions@freebsd.org Received: from sage-one.net (adsl-65-71-135-137.dsl.crchtx.swbell.net [65.71.135.137]) by hub.freebsd.org (Postfix) with ESMTP id 6EA1937B405 for ; Fri, 31 May 2002 08:48:11 -0700 (PDT) Received: from SAGEONE (sageone [192.168.0.5]) by sage-one.net (8.11.6/8.11.6) with SMTP id g4VFm9829934 for ; Fri, 31 May 2002 10:48:10 -0500 (CDT) (envelope-from jackstone@sage-one.net) Message-Id: <3.0.5.32.20020531104808.01c49f08@mail.sage-one.net> X-Sender: jackstone@mail.sage-one.net X-Mailer: QUALCOMM Windows Eudora Pro Version 3.0.5 (32) Date: Fri, 31 May 2002 10:48:08 -0500 To: freebsd-questions@freebsd.org From: "Jack L. Stone" Subject: DD for HD backups Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" 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 Running 4.5-RELEASE This is more of an answer than a question... for the archives and the next who may wonder about using dd to safely duplicate a hard disk & within a reasonable amount of time. A few days ago, I had asked about using dd to backup from one HD to another. I wondered how long it would take for 10GB... at least a ballpark guess would be good enough. The answer I got was that it depends on the hardware, such as CPU, RAM, etc. Well, last night, I dove in first using my test box with two identical 10GB HD. The objective was to move up to the production boxes, each with two identical 40GBs. Here's the stats: TEST BOX: 200MHz 96MB RAM 2 10GB HDs (old HDs) started 8:29pm done 9.04pm = 35mins cpu 7-10% 1252755+0 records in 1252755+0 records out 10262568960 bytes transferred in 2122.415942 secs (4835324 bytes/sec) NOW, the BIG question: "would the HD-2 boot up and function exactly like the HD-1..??" ANSWER: YES! I merely switched the cables, rebooted and VOILA! PRODUCTION BOX #1: 1.2GHz RAM 1GB 2 40GB IDEs ATA100s started: 9:34pm done: 10:23pm = 49 mins root@asafeserver>> dd if=/dev/ad0 of=/dev/ad1 bs=8192 4885335+0 records in 4885335+0 records out 40020664320 bytes transferred in 2952.664701 secs (13554084 bytes/sec) PRODUCTION BOX #2: 1.4GHz 1GB RAM 2 40GB IDEs ATA100s Started 9:46am 10:25am =39 mins root@sage-one>> dd if=/dev/ad0 of=/dev/ad1 bs=8192 4886112+0 records in 4886112+0 records out 40027029504 bytes transferred in 2359.703037 secs (16962740 bytes/sec) I am pleased..... .... our website: http://www.sage-one.net/ Best regards, Jack L. Stone Server Admin To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message