On 06/15/15 12:54, Liviu Daia wrote: > On 15 June 2015, Nick Holland <[email protected]> wrote: > [...] >> In the first case, an rsync-based backup is probably almost impossible >> to beat. Combine with the --link-dest option (google for it. the >> man page is accurate, but you won't probably understand the full >> implications of this. When you are grinning from ear-to-ear and >> saying "oh wow" over and over, you got it), you can have rotated >> backups with minimal BW and disk usage, AND files on the backup system >> are directly viewable and usable (and every backup after the first >> is incremental, and every backup directory is a "full"). I've used >> systems like this for over a decade now, and I can't over-state how >> powerful and useful they are BEYOND simple backup and restore, I keep >> finding new uses for this type of system. Downside: can't really >> do bare-metal restores, and when crossing OSs, I've had issues with >> ownerships and permissions. > [...] > > The other downside, if you use the --link-dest option, is that > there's always only one copy of each file. A few days ago there was > a post on SO by somebody who used that system, and found out that his > backup disk had bad sectors in the middle of some large files. He > wasn't amused.
This has nothing to do with --link-dest, really. If your disk has bad spots, you will hope it was only one large file...usually, it's the whole disk you can't read. For any disk-to-disk system -- rsync, dump/restore, etc, you need some kind of "more than one copy, more than one place" solution, too. Disk-to-Disk doesn't change the rules of backups: multiple copies, off-site, etc. I kinda hoped that was understood, but that was probably my error. Nick.
