There are many jj2 hamachi servers, the best way to let ppl join your servers is to name your server like this (or close to it):

Hamachi [network name] [network password]

So my server would be:

Hamachi - jjrnetwork4 - no pas


The 4 is because its the 4th network, a network can only have 16 ppl unless you pay for it. So be alert for when your hamachi is full.

(And yes, sometimes ppl join: I once had a server with like 6 ppl with only doing this)