Pair your second device
On the same network, point one device at the other's address. Pairing is mutual —
the second device has to approve it, so nobody can pair with you unilaterally.
$ opensave pair 192.168.1.42
# then on the other device:
$ opensave pair requests
$ opensave pair approve node_a1b2c3…
On different networks instead? Run opensave relay join <code>
with the same made-up code on both devices and they'll find each other through the
relay — no port forwarding, and the relay stores nothing. From 2.4.0, what passes
through it is sealed end to end between your two devices, so the relay forwards
saves it cannot read.