I buy vpn server because he was ready tutorial.
I use this tutorial https://www.digitalocean.com/community/tutorials/how-to-set-up-an-openvpn-server-on-ubuntu-16-04 to configure openvpn, copy and paste.
This configuration works fine, but I have one problem.
How to set that the client can send ping to server, server to client, and client to other client.
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