Fix openvpn mbuf packet dropped Written by Mirabellette / 11 april 2018 / no comments Hello everyone I hope you are going great and everything was fine for you. Use case I have an openvpn daemon running with TCP on 443 port on a Debian system. I got thousands of error messages since months about MBUF packet dropped. The message was openvpn MBUF: mbuf packet droppedIt occurs only if you use openvpn over TCP. I know it is considered to be a bad practice because it unneeded traffic but you have to make choice. What I do After hours of research, I was able to fix it. I add this two lines to the server configuration file: tcp-queue-limit 4096 bcast-buffers 4096 Now, you have to restart openvpn with this command : systemctl restart openvpn or service openvpn restart if systemd isn't installed on your system. You should not see this message in log anymore \o/ and get a little bit more stable connection thanks to the undropped packet. Sources https://forums.openvpn.net/viewtopic.php?t=24313 http://thread.gmane.org/gmane.network.openvpn.user/35619 Social media If you find this article interesting, feel free to subscribe to my RSS flux and to follow me on Mastodon. Don't hesitate to share it if you think he could interest someone else.