I recently ran into a problem where my computer can no longer wake properly from sleep, forcing me to shut it down every night. It made me realize I should have system snapshots available in case an update or configuration change breaks something. I already back up my personal files to a separate external drive, so I mainly want Timeshift for restoring system files and settings.
My understanding was that Timeshift backs up everything by default, but I've since read that it normally excludes /home. Should I include the system directories while excluding /home, or is that already the default configuration? If an update causes a problem, can I restore a Timeshift snapshot while leaving my personal files untouched?
Also, what is the recovery process if the system becomes unbootable or I can't log in? My external drive is formatted for use with Windows and contains other backups, so I'd prefer not to reformat it unless necessary. Are there alternatives that can store a system backup on that kind of drive?
2 Answers
That is essentially Timeshift’s normal behavior. It is intended to protect system files and settings while excluding /home, so restoring a snapshot can undo a troublesome update without replacing your personal files. Check the snapshot settings before relying on it, since the include and exclude lists can be changed manually.
If the installed system will not boot, start a live Linux USB and install or run Timeshift from there. Mount the system and snapshot drive, select the snapshot, and restore it from the live environment. It’s worth testing that the snapshot disk is accessible before you need it, and keeping a live USB available. Timeshift is mainly for system recovery, not protection against a failed or corrupted drive.
That clears up my confusion. I may have changed the defaults when I first set it up and then forgotten about it, so I’ll verify the exclusions before creating new snapshots.