Configure unison for continuous sync

unison.md

Configure unison for bi-directional sync

1. On client

1. Create a profile (~/.unison/bidirsync.prf):

# Unison preferences
label = bi-directonal sync with server
root = /home/<user>/git
root = ssh://<user>@<server-name>//home/<user>/sync/git
sshargs = -oIdentityFile=/home/<user>/.ssh/<privkey-name>
batch = true
auto = true
repeat = watch
logfile = /home/<user>/.unison/unison.log
#debug=all

2. Test the profile with unison bidirsync

Create systemd job

1. Create the directory mkdir -p ~/.config/systemd/user
2. Add file unison.service:

[Unit]
Description=Unison

[Service]
Environment="PATH=/usr/bin"
ExecStart=/usr/bin/unison bidirsync
#%i
Restart=always
RestartSec=10

[Install]
WantedBy=default.target

3. Start/stop the job: systemctl --user {start|stop} unison
4. Check status: systemctl --user status unison
5. Enable/disable background job: systemctl --user {enable|disable} unison

2. On client and server

1. Download depwndencies: sudo apt-get install ocaml python-pyinotify
2. Download unison from https://github.com/bcpierce00/unison/releases
3. Unpack
4. Build and install: make NATIVE=false && make install (binaries go to ~)

Optional setup

Depending on the number of files to watch it may be required to increase the number of files that can be watched: echo fs.inotify.max_user_watches=500000 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p