Date: Tue, 3 Aug 2004 09:53:40 -0400 (EDT) From: Jerry McAllister <jerrymc@clunix.cl.msu.edu> To: wmoran@potentialtech.com (Bill Moran) Cc: Matt <finitesoup@gmail.com> Subject: Re: using a disk "mirrored" with dd Message-ID: <200408031353.i73DreN26979@clunix.cl.msu.edu> In-Reply-To: <20040803093705.6dec1f13.wmoran@potentialtech.com> from "Bill Moran" at Aug 03, 2004 09:37:05 AM
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> > Matt <finitesoup@gmail.com> wrote: > > > I have a machine running 4.10-RELEASE-p2 with two identical hard disks > > -- ad0 and ad2. I would like to make a complete copy of the first disk > > to the second disk nightly for quick disaster recovery. > > > > I've dd'ed the disk as follows > > > > # dd if=/dev/ad0 of=/dev/ad2 > > > > and edited the disklabel of the second disk to change ad0s1 to ad2s1 as follows > > > > # disklabel -e -r ad2 > > > > However, I'm still unable to mount the root partion (or any other > > partition) of the second disk to tweak /etc/fstab etc. even though > > > > # mount /dev/ad2s1a /mnt > > mount: /dev/ad2s1a: Operation not permitted Not an answer to your specific question, but I would suggest doing the whole thing a little differently. First fdisk, disklabel and newfs the drive to make the filesystems you want, including making the slice bootable, etc. Then copy each filesystem on the previous disk using dump(8)/restore(8). If you have enough scratch space, you can dump to files in spare space and then restore from those. Or, you can pipe a dump to a restore. It is preferable to using dd for something like this. ////jerry > > What is your securelevel? See man securelevel. > > > > > What am I missing? Is there anything else I need to do beyond editing > > the disklabel to allow me to use the "mirrored" disk? > > > > Output of disklabel for the two disks follows: > > > > # disklabel ad0 > > # /dev/ad0c: > > type: ESDI > > disk: ad0s1 > > label: > > flags: > > bytes/sector: 512 > > sectors/track: 63 > > tracks/cylinder: 255 > > sectors/cylinder: 16065 > > cylinders: 4864 > > sectors/unit: 78156162 > > rpm: 3600 > > interleave: 1 > > trackskew: 0 > > cylinderskew: 0 > > headswitch: 0 # milliseconds > > track-to-track seek: 0 # milliseconds > > drivedata: 0 > > > > 8 partitions: > > # size offset fstype [fsize bsize bps/cpg] > > a: 409600 0 4.2BSD 2048 16384 97 # (Cyl. 0 - 25*) > > b: 5242880 409600 swap # (Cyl. 25*- 351*) > > c: 78156162 0 unused 0 0 # (Cyl. 0 - 4864*) > > e: 4194304 5652480 4.2BSD 2048 16384 89 # (Cyl. 351*- 612*) > > f: 10485760 9846784 4.2BSD 2048 16384 89 # (Cyl. 612*- 1265*) > > g: 18874368 20332544 4.2BSD 2048 16384 89 # (Cyl. 1265*- 2440*) > > > > # disklabel ad2 > > # /dev/ad2c: > > type: ESDI > > disk: ad2s1 > > label: > > flags: > > bytes/sector: 512 > > sectors/track: 63 > > tracks/cylinder: 255 > > sectors/cylinder: 16065 > > cylinders: 4864 > > sectors/unit: 78156162 > > rpm: 3600 > > interleave: 1 > > trackskew: 0 > > cylinderskew: 0 > > headswitch: 0 # milliseconds > > track-to-track seek: 0 # milliseconds > > drivedata: 0 > > > > 8 partitions: > > # size offset fstype [fsize bsize bps/cpg] > > a: 409600 0 4.2BSD 2048 16384 97 # (Cyl. 0 - 25*) > > b: 5242880 409600 swap # (Cyl. 25*- 351*) > > c: 78156162 0 unused 0 0 # (Cyl. 0 - 4864*) > > e: 4194304 5652480 4.2BSD 2048 16384 89 # (Cyl. 351*- 612*) > > f: 10485760 9846784 4.2BSD 2048 16384 89 # (Cyl. 612*- 1265*) > > g: 18874368 20332544 4.2BSD 2048 16384 89 # (Cyl. 1265*- 2440*) > > > > Thanks for any insight, and let me know if you need to see anything else. > > > > -Matt > > _______________________________________________ > > freebsd-questions@freebsd.org mailing list > > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > > To unsubscribe, send any mail to "freebsd-questions-unsubscribe@freebsd.org" > > > -- > Bill Moran > Potential Technologies > http://www.potentialtech.com > _______________________________________________ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscribe@freebsd.org" >
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