Date: Fri, 28 Sep 2001 17:40:06 -0700 (PDT) From: kjerste soderberg <kjerstes@yahoo.com> To: Kevin Oberman <oberman@es.net> Cc: freebsd-mobile@freebsd.org Subject: Re: cloning laptop drives Message-ID: <20010929004006.87936.qmail@web9704.mail.yahoo.com> In-Reply-To: <200109282350.f8SNo6k20026@ptavv.es.net>
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OK I AM NOW FINISHED with this issue my thanx to ALL respondents. Truly world class tech suppt delivered promptly. Here's what I settled on and it is presently working fine and I can transfer 15.2MB/sec so cloning each 20GB drive is taking on ave 20min approx. I am posting this final note for future reference by future generations who will run into same problems when "mass-producing" FBSD or any unix. Again thanx to all, pls see Kevin's response below for more valuable insights, and with this last response in mind here's the documented procedure. --CLONING IDENTICAL DRIVES WITH dd-- Doing this on a 1.4GHz AMD desktop (512MB RAM) 1st drive IS THE BOOT drive on ide channel 1 2nd drive is the target drv on ide channel 2 1.) boot machine into single user (and / mounted as RO) catch the spinning proppeler when booting (I believe it's called 3rd stage loader?) by typing any character, then `set hw.ata.wc=1` and then `boot -s`. Now in single user mode. 2.) `dd if=/dev/ad0 of=/dev/ad2 bs=2048k` tried diffrent buffers of 1024k, then 4096k. This buffer of 2MB worked fastest in this configuration. <ctrl-t> during dd yields progress. note: due to a lack of proper ATA100 cables that have 2 connectors each, ended up using just the 2 drives each run, so that's why mounting ad0 as boot(RO) AND source drive and then ad2 as target on 2nd ide channel. SO I'm doing this 20 times for the 20 drives. note: couldn't get `buffer` command (after installing port) to behave correctly so ended up not using it, maybe I didn't put enough time into it but this procedure does end up being very efficient even without `buffer` ... --- Kevin Oberman <oberman@es.net> wrote: > > Date: Fri, 28 Sep 2001 15:53:45 -0700 (PDT) > > From: kjerste soderberg <kjerstes@yahoo.com> > > > > Thank U for this valuable advice > > can I ask; > > > > --- Kevin Oberman <oberman@es.net> wrote: > > > As others have pointed out, ......I would > strongly > > > recommend setting hw.ata.wc=1 during the boot. > > > > do I set this in /boot/loader.rc or can I somehow > set > > it on the command line much like booting into > single > > user (ie: boot -s) at the kernel prompt? > > I'm told that you can use the command: > set hw.ata.wc=1 > at the boot prompt, but I don't know if it needs to > be done at the > first boot prompt (from loader) or at the later > prompt where you do > boot -s. > > You can add the line: > hw.ata.wc="1" # Turn on write-cache on ATA disks > to /boot/loader.conf. This is probably not that bad > an idea. There has > been endless discussion of the safety of running > with write cache > enabled on ATA disks. Most all the gurus run with it > enabled and Matt Dillon > (who wrote the FreeBSD VM system and lots of other > stuff) reports that > there has never been a documented case of major data > loss due to disk > caching. He turns it on. There is a REAL chance of > minor loss in the > event of power failure as the data written to cache > but not dumped to > the disk will be lost. > > Or, just upgrade to 4.4 and it will be on by > default. > > > > I assume you are doing the clone with the system > > > booted stand-alone and filesystems unmounted > > > > yes, I was advised by many here to make certain > the > > drives (both source& target) are unmounted.. > > > > > Don't expect any sign of disk activity except > the > > > LED. > > > > ANother respondent advised me to do ctrl-T which > does > > give me a progress rept and I was also advised to > do a > > This shell dependent, but, if your shell supports > it, go for it! > > > `systat -vmstat 1` for progress but I can't do > this as > > I am in single user mode .. > > > > Thanx for your advise as well, truly appreciated.. > > FWIW, here is my laptop clone script. It clones two > slices, one > containing Windows and one containing FreeBSD. Takes > 14 minutes to > clone 6 GB of data. I clone a 4 GB and a 2 GB slice > on a 12 GB drive > to identically sized slices on a 6 GB drive. Drives > are UDMA33 on > separate controllers. > > #!/sbin/sh > dd bs=32k if=/dev/ad0s1 of=/dev/ad2s1 > dd bs=32k if=/dev/ad0s2 of=/dev/ad2s2 > > R. Kevin Oberman, Network Engineer > Energy Sciences Network (ESnet) > Ernest O. Lawrence Berkeley National Laboratory > (Berkeley Lab) > E-mail: oberman@es.net Phone: +1 510 486-8634 __________________________________________________ Do You Yahoo!? Listen to your Yahoo! Mail messages from any phone. http://phone.yahoo.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-mobile" in the body of the message
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