--- title: "unison" tags: [ "Documentation", "Backups" ] --- Install unison on both machines, and on both make the `~/.unison` directory. Make a job called `backup`: > vim ~/.unison/backup.prf All jobs must end in `.prf`. Here is an example job, which synchronizes the `~/music` directory with a remote machine. ``` auto = true root=/home/ghost root=ssh://ghost@192.168.0.10//home/ghost/ path=music ignore=Name *.flac ``` The last command means it will ignore any file with a name ending in `.flac`. ## Automatic Runs The first command means this will run but also confirm which files will be deleted, and which will be transferred, us `batch = true` instead. Set unison to run with crontab or a systemd unit file to have directories synchronize automatically. ## Problem Solving Unison is extremely sensitive to version changes. Both machines must have exactly the same version of unison installed, as well as the same version of `ocaml`. Check with: > unison -version You will see data files summarizing what has happened in the `~/.unison` directory. If something goes wrong, you may be prompted to delete these to start again.