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On Wed, Mar 7, 2012 at 8:55 AM, <gandalf@××××××××××.uk> wrote: |
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>> Hi, |
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>> I'm interested in the idea of cloning a live, complicated hardware |
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>> system onto a single external hard drive as a simple backup. I would |
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>> like this external drive to be completely bootable. What's the best |
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>> way to approach doing this? I was considering just doing a Gentoo |
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>> install from scratch but figured maybe there's a way to clone enough |
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>> of the live system to get me there less painfully? |
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>> |
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>> The system I'm playing with has five 500MB hard drives with most |
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>> partitions in linked together in various forms of RAID. (1, 5 & 6) |
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>> That said, the total storage that this system presents KDE and the |
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>> users is about 600GB. |
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>> |
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>> I have an external 1TB eSATA drive which is therefore large enough |
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>> to hold everything on this system, albeit without the reliability of |
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>> RAID which is fine for this purpose. |
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>> |
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>> The system looks more or less like: |
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>> |
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>> /dev/sda1 -> /boot (50MB) |
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>> /dev/sdb1 -> /boot copy |
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>> /dev/sdc1 -> /boot copy |
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>> |
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>> c2stable ~ # df |
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>> Filesystem 1K-blocks Used Available Use% Mounted on |
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>> rootfs 51612920 31862844 17128276 66% / |
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>> /dev/root 51612920 31862844 17128276 66% / |
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>> rc-svcdir 1024 92 932 9% /lib64/rc/init.d |
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>> udev 10240 476 9764 5% /dev |
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>> shm 6151284 0 6151284 0% /dev/shm |
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>> /dev/md7 389183252 350247628 19166232 95% /VirtualMachines |
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>> tmpfs 8388608 0 8388608 0% /var/tmp/portage |
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>> /dev/sda1 54416 29516 22091 58% /boot |
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>> c2stable ~ # cat /proc/mdstat |
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>> Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] |
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>> [raid4] |
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>> md6 : active raid5 sdb6[1] sdc6[2] sda6[0] |
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>> 494833664 blocks super 1.1 level 5, 64k chunk, algorithm 2 [3/3] |
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>> [UUU] |
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>> |
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>> md7 : active raid6 sdb7[1] sdc7[2] sda7[0] sdd2[3] sde2[4] |
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>> 395387904 blocks super 1.2 level 6, 16k chunk, algorithm 2 [5/5] |
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>> [UUUUU] |
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>> |
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>> md3 : active raid6 sdb3[1] sdc3[2] sda3[0] sdd3[3] sde3[4] |
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>> 157305168 blocks super 1.2 level 6, 16k chunk, algorithm 2 [5/5] |
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>> [UUUUU] |
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>> |
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>> md126 : active raid1 sdc5[2] sda5[0] sdb5[1] |
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>> 52436032 blocks [3/3] [UUU] |
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>> |
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>> unused devices: <none> |
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>> c2stable ~ # |
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>> |
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>> /dev/md3 is a second Gentoo installation that doesn't need to be |
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>> backed up at this time. md6 is an internal RAID used to back up md7 |
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>> daily. It doesn't need to be backed up, but if the machine totally |
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>> failed killing all the drives that wouldn't survive so currently I |
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>> back up md126 to md6 daily, and then back up md6 weekly to an external |
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>> eSATA drive. |
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>> |
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>> What I'd like to do is clone |
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>> |
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>> 1) /boot (sda1) including grub and everything required to make it bootable |
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>> 2) back up the system portions of dev/md126 (/ ) |
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>> 3) Add some swap space on the external drive |
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>> 4) back up /dev/md7 which is all of my VMs |
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>> 5) back up /home to a separate partition on the external drive |
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>> 6) back up some special things like /var/lib/portage/world and |
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>> /usr/portage/packages |
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>> |
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>> My thought is that this drive is basically bootable, but over time |
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>> gets out-of-sync with the system. However should the system fail I've |
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>> got a bootable external drive with all the binary packages required to |
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>> get it running again quickly. However I can always boot the drive, do |
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>> an emerge -ek @world, and basically be back to where I am as of the |
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>> last backup. |
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>> |
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>> The external drive will look something like: |
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>> |
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>> /dev/sdg1 -> /boot |
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>> /dev/sdg2 -> swap |
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>> /dev/sdg3 -> / (not including /home, /usr/portage/distfiles, etc) |
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>> /dev/sdg5 -> /usr/portage/packages |
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>> /dev/sdg6 -> /dev/md7 |
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>> |
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>> etc.... |
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>> |
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>> I will of course have to modify grub.conf and /etc/fstab to work |
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>> from this drive but that's no big deal. |
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>> |
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>> What are folks best ideas about how to approach doing something like |
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>> this? |
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>> |
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>> Thanks, |
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>> Mark |
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>> |
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>> |
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> Hi, |
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> Why don't you something like bind mount the folders you want to copy |
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> and rsync them to the eSATA disk, after creating a similar partition |
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> layout on it. Remember to exclude system files like /proc/*, /dev/* |
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> and /sys/* as well as the ones you want to exclude yourself from the |
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> rsync. When you want to sync the clone again just do the same again |
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> and rsync the changes. |
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> |
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> Regards, |
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> Derek |
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> |
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> |
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|
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As an added note on this, rsync's --one-file-system (-x) flag is handy |
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for avoiding grabbing unneeded things, but will typically leave you |
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without the base few device nodes needed to boot the backup, those can |
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either be grabbed from a stage3, or created with (courtesy of Linux |
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From Scratch's section "6.2.1. Creating Initial Device Nodes"): |
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|
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mknod -m 600 ${backup}/dev/console c 5 1 |
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mknod -m 666 ${backup}/dev/null c 1 3 |
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|
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-- |
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Poison [BLX] |
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Joshua M. Murphy |
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