Docker network issues?

Hi i have been trying to run one container as a vpn client and let other containers use that tunnel like described here.

but when i do it i can only access the connected containers from or localhost, when i try with the ip of my rockstor machine nothing happens and it eventually times out (i tested with curl on the server).

when i do the same thing on my desktop machine it works as expected both for ip, and localhost.

i’m wondering if this is some setting giving me this issue or if it might be because of the old version of docker running on the server?