title: Ubuntu 22.04 OpenVpn server error: write to TUN/TAP : Invalid argument (code=22)
body: <p>I start openvpn server with <code>openvpn --dev tun --ifconfig 172.16.0.1 172.16.0.2 --cipher AES-256-CBC</code> on my Ubuntu 22.04 Linux Box</p>
  <p>I generate the certificates and keys with easycert and copy everything on a Windows 10 client.</p>
  <p>The connection doesn't work, and in the syslog I find a lot of</p>
  <pre><code>write to TUN/TAP : Invalid argument (code=22)
  write to TUN/TAP : Invalid argument (code=22)
  ...
  </code></pre>
  <p>What's wrong? This is my client configuration file:</p>
  <pre><code>client
  dev tun
  proto udp
  remote *MYSERVERIP* 1194
  resolv-retry infinite
  nobind
  persist-key
  persist-tun
  ca ca.crt
  cert client.crt
  key client.key
  remote-cert-tls server
  cipher AES-256-CBC
  
  </code></pre>