[nflug] Verifying a cdrom image backup, some ideas

[Daniel V]

Joe, please refresh my memory here, what GNU/Linux distribution are you using? Are you using IDE or SATA disk drives? 

A simple solution to backing up is to use partimage (http://www.partimage.org/Screenshots). It also comes in SystemRescueCd (http://www.sysresccd.org), a boot-up CD-ROM distro.

You could just backup your setup, but things change so quickly in GNU/Linux, that I think it's better for you to set back up your data and then redo your install and then transfer data over. Example, I like using Sylpheed for email, so I backup the two relevant directories. Whatever distro I'm using, CentOS, Knoppix, Ubuntu, will at some point invariably install the latest Sylpheed is in their repository. I was using Sylpheed stable in a Knoppix virtual machine and then when Sylpheed 2.50 came out I backed up the directories and installed the latest Ubuntu on another machine and then installed Sylpheed, which was a new version than what was on Knoppix at the time. The new Sylpheed in Ubuntu immediately worked with the old data and all is good. Now Sylpheed is updated again, but I don't have time to try to compile from source, so I'll probably just wait for Ubuntu 9. I haven't looked at the changelog for the newest Sylpheed yet, so I don't know yet if I
 have a compelling reason to upgrade.

A few things that might affect potential start-up from an external drive.
If you use an Intel motherboard, you might be able to use the Intel Extensible Firmware Interface (EFI) Boot Manager. Or you might be able to use the SuperGrubDisk CD-ROM (http://www.supergrubdisk.org/).

Daniel

--- On Mon, 12/15/08, Joe <josephj at main.nc.us> wrote:

> From: Joe <josephj at main.nc.us>
> Subject: Re: [nflug] Verifying a cdrom image backup
> To: nflug at nflug.org
> Date: Monday, December 15, 2008, 3:34 PM
> That sounds even simpler than what I'm trying to do now, but how easy i
> it to verify that it worked? I guess I just have to unplug my main drive
> and put the backup one in. That's not too tough, but I don't really want
> to pull my system apart every time.
> 
> I have a removable drive bay I could use that holds my current backup
> drive. What I don't know is how to set the machine up so lilo can boot
> from the backup drive as an option on its menu.
> 
> Joe
> 
> SilverBear wrote:
> > Well, I agree it's best to keep data separate, and
> backed up separately.  But a person might also have his OS
> tweaked "just so." Reinstalling and then
> dl/installing  all the right packages could be a hassle.
> >
> > With prices as low as they are these days, a separate
> backup HDD that can mirror selected partitions, including
> OSs, is quite practical. It needn't be always mounted
> --or even physically connected-- just so long as it's
> convenient to attach to the system when needed.
> > Backing up a whole 8GB OS partition with dd from a
> liveCD usually takes 15-20 minutes or so, if I remember
> correctly. I have 2GB RAM, so adjust for that. Yes, disk
> write and bus speeds play a large part in how soon a dd
> command will complete large amounts of data, but RAM seems
> to factor in as well.
> >
> > John
> >
> >   
> >> -----Original Message-----
> >> From: cloudlakedreamer at yahoo.com
> >> Sent: Sun, 14 Dec 2008 13:34:41 -0800 (PST)
> >> To: nflug at nflug.org
> >> Subject: Re: [nflug] Verifying a cdrom image
> backup
> >>
> >> Who has time to mess with restoring from lots of
> CD-ROM's ? I backup my
> >> data, and then if necessary, I'll just
> reinstall, then come back and
> >> restore my scripts, my email, etc... Just an idea,
> it might save you a
> >> lot of time.
> >>
> >> Daniel
> >>
> >>
> >> --- On Fri, 12/12/08, Christopher Hawkins
> <chawkins at bplinux.com> wrote:
> >>
> >>     
> >>> From: Christopher Hawkins
> >>> Subject: Re: [nflug] Verifying a cdrom image backup
> >>> re: mondorescue ... you might just download ... see how they do verification.
...
> >>> restore it and then compare. Maybe restore then rsync -avn 
>... original_dir/* restored_dir/
> >>>
...
> >>> ----- Original Message -----
> >>> From: "Joe"
> <josephj at main.nc.us>
> >>> Sent: Friday, December 12, 2008 2:39:30 AM GMT
> >>> ... making image backups of my system in chunks that
> >>> fit on cdroms.
> >>> ... using dump... md5sums ... do not match...
> >>>
> >>> I just ran a 15 cdrom backup that worked fine,
> but I realized afterwards that since the root file system was mounted,
> the backup was probably useless, so I recreated it using a livecd with
> the root unmounted.
> >>> That's the one I'm having trouble verifying now.
> >>> Am I doing something wrong?
> >>> How do I verify that what I wrote to the cdrom
> is identical to the image on disk and is completely readable - a
> reliable/restorable copy?
> >>> TIA
> >>> Joe