Ubuntu
openvpn package

  1. Bug #1934781
  2. Comment #0

Comment 0 for bug 1934781

Revision history for this message
Nils Toedtmann (m-launchpad-net-mail-nils-toedtmann-net) wrote :

See upstream bug reports:
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=968942
- https://community.openvpn.net/openvpn/ticket/1208

Openvpn < 2.4.8 opens the TCP port with a too small backlog, and on kernels > 4.3 that leads to incoming connections being dropped. This kernel message is a symptom:

  TCP: request_sock_TCP: Possible SYN flooding on port 1194. Dropping request. Check SNMP counters.

I experienced this on a Bionic 18.04.5 (after having upgraded from Xenial) with openvpn 2.4.4-2ubuntu1.5

Fixed upstream.