rebuild system from dump tape
 

Hi all - I have a Red Hat Enterprise (AS) 4.8 system and I need to know how to totally rebuild the system from dump tape. I have been making some full level 0 dumps of the system to the attached DAT72 tape drive... In the case the boot disk goes south, I need to reload from tape, onto a new disk drive. I know how to do this in Solaris. I assume you boot from CD to like a mini-root, then configure and mount the drive on temp mount points, restore the sys data, then load the "boot blocks" (like installboot on solaris)... Can anyone help?

Sorry, to my knowledge, you don't/can't make a 'dump tape' (mksysb, etc.), for Linux.

There are alternatives, however. Look into mkcdrec, systemimager, and mondoarchive. All of them can make bootable images of an entire system. They can even let you keep the system in one .ISO image, suitable for booting over the network, or you can burn individual ISO's to CD or DVD, for physical booting.

Hi - Oh sorry, I did not mean I wanted a "one step" solution (like mksysb, flasharchive, or ignite...) I was figuring that it would be something like a Sun/Solaris type of rebuild:

(1) boot cdrom to get a mini unix loaded in ram
(2) go in and create the filesystems
(3) mount a filesystem
(4) restore tape fileset
(5) mount the next filesystem
(6) restore the next tape fileset
(7) etc...
(8) install the bootblocks

Does anyone have the reqd steps to perform?

Thanks

Well... that's close to the process I'd try. To be sure you can even try to do this, though, I would create a generic tape on the current system, say using tar. (You don't need to put much on it; just something readily identifiable.) Then boot off the CD you are thinking of using as your recovery system. Make sure you can issue a "tar tvf" command and see all the files you copied to tape. I think it's safe to assume that if you can read the tar archive from tape when booted from the CD you should have the ability to read your dumps. (The drivers are loaded, etc.)

That said, though, you'll need a dump executable or something similar. It's option on SuSE (at least /I/ didn't select it during the initial install but YaST shows it as available) but the most important thing is to make sure it's available on your boot CD. If it's not, you might want to use a file-based backup (cpio or even tar). That should also work -- I've used that to do restores of entire disks after replacing disks that started throwing lots of bad block errors -- but it's a bit more work (or at least time consuming) since you have to build the filesystems, check for bad blocks, etc., before you start spinning tapes.

There is no way that I know of to restore the boot blocks by using some tool like installboot. Your rescue CD should be able to reinstall the grub program/boot record. A really clever person might be able to save the boot blocks off onto other media using dd or even onto your root partition where they'd get backed up along with the rest of your files. Then you could "dd" them back into place using a copy of dd on your recovery CD. (I've never done that, though.)

I'd practice whatever procedure you develop on a second system and have an extra disk drive handy to act as the replacement for the disk that "failed" on your practice system. You might need to borrow your tape drive unless you have several just laying around.

Bootable tapes would be so-o-o sweet for bare metal recovery, wouldn't they. (I haven't used any since my VMS days.) Sadly, I doubt the PC architecture supports such a thing.

Good luck...

--
Rick

Yes, and I told them to you in my first post. Any of those utilities do exactly what you're wanting.

Hi Rick - thanks... I'll give it a shot.

pyroman

Sorry..my name's not Rick.