title: TCP: Client sends [RST, ACK] immediately after sending [ACK] to Server
body: <p>I've got nginx 1.9.7 compiled against OpenSSL 1.0.2e running on Ubuntu 14.04.3 LTS (3.13.0-71-generic x86_64). I can connect to it with a browser no problem at all, and get a secure connection.</p>
  
  <p>I also have a client who is running some Windows Server and is trying to connect to using WCF. They report they aren't able to connect to my service.</p>
  
  <p>My nginx error log shows:</p>
  
  <pre><code>2015/12/09 17:38:27 [info] 10750#0: *6494 recv() failed (104: Connection reset by peer) while SSL handshaking, client: {REDACTED}, server: 0.0.0.0:443
  </code></pre>
  
  <p>Digging deeper, a Wireshark dump shows this pattern:</p>
  
  <pre><code>Client -&gt; Server [SYN]
  Client &lt;- Server [SYN, ACK]
  Client -&gt; Server [ACK]
  Client -&gt; Server [RST, ACK]  (connection closes)
  </code></pre>
  
  <p>Sniffing a successful request shows:</p>
  
  <pre><code>Client -&gt; Server [SYN]
  Client &lt;- Server [SYN, ACK]
  Client -&gt; Server [ACK]
  Client -&gt; Server [PSH, ACK] (sends SSL Client Hello)
  </code></pre>
  
  <p>I'm not really a TCP guy, so I'm a little out of my depth in understanding what could be happening here. Any advice would be appreciated.</p>