[Discuss] Dropping obsolete commands (Linux Pocket Guide)

[blu at nedharvey.com (Edward Ned Harvey (blu))]

> From: Daniel Barrett [mailto:dbarrett at blazemonger.com]
> 
> 1. Boot on Knoppix or other "live" CD
> 2. rsync everything from the backup medium to the new disk (using the
> correct
> options to preserve ownership, restore devices & symlinks, etc.)
> 3. Run grub
> 
> Am I missing something? The restored systems seem to run fine.

I don't know. That's the point. Whatever options you give to rsync, are you guaranteed to support every inode type and every extended feature that the filesystem supports? In your usage, does rsync preserve hard links, or make separate copies of the file? Does that cause any unexpected behavior for any of your apps? How does rsync handle sparse files? The level of esoterica is far beyond what anybody should need to think about.

I like to use rsnapshot when I'm backing up specific directories, or specific filesystems, where I'm pretty confident weird stuff doesn't need to be considered. For example, /etc, /root, and /home. I would not rely on rsnapshot or rsync to restore / or /boot, or even /var. But as Daniel points out, it's likely to actually work fine in many situations.

I have no idea when/if weird things like named pipes are still used. A long time ago it was important to preserve character special devices and block devices, but fortunately that's been abstracted and is now generated by kernel at runtime (devfs, or whatever the modern equivalent is).

Around 15 years ago, following "linux from scratch," I needed to manually create major/minor numbers with mknod in /dev to correspond to whatever kernel modules I had compiled in.

In the present day, it's certainly better practice to use configuration management and system build automation tools, and then backup "normal" files using something like rsnapshot or rsync, without dump/restore. But I'm surprised how many people here say they've never used it.