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    Error : openvpn[…]: write UDPv4: No buffer space available (code=55)

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    • J
      jaumont
      last edited by

      I everyone,

      I am trying to used PfSence/OpenVPN/Ospfd and always get the following errors in the openvpn logs:

      openvpn[…]: write UDPv4: No buffer space available (code=55)

      I have been playing with the sysctl variable to solve the issue in vain.

      My current settings are as follow:

      kern.ipc.maxsockets=16448
      kern.ipc.maxsocbufs=4262144
      kern.ipc.nmbclusters=25600

      net.inet.udp.recvspace=262144  # Increase UDP "recieve" windows size to increase performance

      Any ideas on how to solve this issue?

      Thanks,

      Jean Aumont
      jaumont@mediagrif.com

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      • C
        cmb
        last edited by

        This is what happens when you setup broken routing, where your client gets a route to the server IP where it's connecting, within the VPN, and tries to access the server IP by using the tunnel. It has to be able to reach the server outside the tunnel not within it, and basically loops traffic and causes chaos. Don't push or setup routes on your client inside the tunnel for the IP it has to reach outside the tunnel.

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