The best and traditional way that has been there for decades is an rsync and then reinstallation of boot-loader. It works always if you know how it's done.
If you need detailed instructions, I can send you that!
On Tue, Jun 19, 2012 at 10:44 AM, Les Mikesell lesmikesell@gmail.comwrote:
On Tue, Jun 19, 2012 at 12:03 PM, Cal Sawyer cal-s@blue-bolt.com wrote:
You're right - documentation is pretty dire. Guess i'm not alone in hating doing it.
Yes, I really, really wish the stuff they are doing was documented, somewhere, anywhere. Not just how to use the program itself which is supposed to 'just work' unattended once you set it up, but the black magic of how they detect and reproduce all of the hardware, lvm, raid, filesystem, etc. across different distributions and versions.
USB backup is broken due to the order in which path variables get set - sure is lot of fun trawling through the scripts to find out what gets set when. Hope the ReaR maintainers are interested in this and haven't gotten themselves mired in tape archive integration - i would have thought USB backup was the winner in terms of getting broad acceptance as a bare-metal DR solution.
USB is sort of 'hands-on' for something that should be unattended, and adds a lot of unpredictable messiness in drive detection, boot order, etc. All you really have to do is export some NFS space and point ReaR to it. At least that is the easy way to get started. If you have another Linux box, just plug your USB drive in there and access it over NFS... problem solved.
Clonezilla-live plays in this space too, but it doesn't do raid or multiple disks at once, and you have to shut down to take the image.
My 'ideal' system would be to have ReaR generate a directory of what will be on the boot iso leaving that somewhere on the host without actually making the image. Then use backuppc to back up the whole host and its normal duplicate-pooling mechanism will keep the extra copies of the tools from taking extra space. Then when/if you need a bare-metal restore, you would first grab the directory of the iso contents, burn a boot CD, let that reconstruct the filesystem, then tell backuppc to restore to it. That way would be completely automatic and always be up to date, with the advantage of backuppc's efficient storage and easy online access to individual files and directories. If you don't mind wasting a small amount of space for the isos, I think that approach would already work if you tell ReaR to just make the boot image and to wait for an external program to do the restore after the filesystem has been rebuilt.
However, when it works - wow. Just restored an HP dl360 w/HWRAID to a Presario desktop machine and it lives! No network, but that's small beans compared to the larger win.
Yes, I've even modified the filesystem layout file to go from a software RAID to a non-RAID, and to change partition sizes during the restores. If it was documented, that capability by itself would be fantastic.
-- Les Mikesell lesmikesell@gmail.com _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos