Using rysync to mirror entire system - what to omit
I have two identical hard drives, and have used dd to make one a duplicate of the boot drive.
I have set up rsync (as root) to run nightly to mirror the backup drive from the boot drive. There are a bunch of directories/files that fail (mainly is /sys) due to lack of permission - some of the sys files are write-only.
Can someone suggest what directories I can exclude from the mirroring?
I would like to be able to either boot the backup drive in case of a boot drive failure, or reinstall Ubuntu on a new disk, then copy the files back from the backup (or use dd, or whatever)