UNIX for Dummies Questions & Answers

In my present dual boot (Fedora Core 4 & WinXP2003 Server) desktop computer, I have redundant 100GB disk drives.

Every so often I boot fedora core 4 and

telinit 1
cp /dev/sda /dev/sdb

and then I reverse the connections to the drives so I boot from the newly created copy.

I just ordered two NSLU2 NAS controllers and two external 300GB USB drives on sale. I would like have a nightly job perform rsync.

I assume I'll have the option of either plugging the 300GB drives directly into the USB ports in the back of my desktop computer or using the NSLU2 NAS controllers.

With the new drives can I just say "telinit 1; cp /dev/sda /dev/sdc" to create a dual bootable image on my new disk that I can subsequently keep up to date with rsync?

If so, can I do that with the NAS controller or do they have to be plugged into the USB port on the back of desktop computer?

My guess is no. Instead I think I'll have to build new dual boot partitions on the disks.

If I do that, can I subsequently use rsync to keep my spare boot disks up to date?

I assume I'll be able to configure my computer to network boot over the NAS controllers too. I understand that the NAS controllers will have to be on my local network for this to be feasible.

Thanks,
Siegfried

You wnat a backup ? rsync is fine no need for cp. exspecial not on the disklevel since this is a real problem when the disk are not totaly equal. i would use dd at least.
but recreating the filesystem by hand an using rsync afterwards is easy.

What exactly is is a bootable disk for you ? what do you exspect when a disk fails ?
so far i know most systems wait until manual intervention if boot fails. a filesystemcopy
may be good enought i most cases.

Simply prepare a cdrom/floppy/usbstick/... with a bootloder an a menu that is ready to start from the backup disk. (normal pc-bios is very crappy when it comes to such tasks).

So if I have a new emtpy disk rsync will correctly create two boot partitions: one for windows and one for Fed Core 4? Wow! I thought I needed cp for that. I presently use it for that.


Could you elaborate further?

cp presently creates a bootable disk for me presently: I can boot windows or fed core 4. Remember I'm doing a "telinit 1" and I'm performing a vertbatim block level copy by specifying /dev/sda. This ignores any filesystems hence it copies the master boot records, all my grub stuff and my windows paritition.

I'm already using grub and I assume I can enhance it's boot menu. Is there any reason to move grub from my internal disks to a USB stick or floppy?

Thanks,
Siegfried