Unison.
<a href="https:&#x2F;&#x2F;www.cis.upenn.edu&#x2F;~bcpierce&#x2F;unison&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.cis.upenn.edu&#x2F;~bcpierce&#x2F;unison&#x2F;</a><p>It handles file conflicts, which is massively critical for anyone thinking of rolling their own.  It also works over ssh, so it&#x27;s encrypted.