title: Restrict cipher suite selection using Openssl s_server
body: <p>I want to test my client against a test server, so I am using OpenSSL s_server command. The goal is to configure the server to select only 1 cipher suite which I configure. This way I can test different cipher suites sent by client. I cannot change the cipher suit list on the client side.</p>
  <p>To start the server I use:</p>
  <pre><code>`{` openssl s_server -accept 50000 -cert ../server/server_certificate.pem -key ../server/private_key.pem -CAfile ca_certificate.pem  -cipher ECDHE-RSA-AES256-GCM-SHA384 -serverpref -state -debug -status_verbose }
  </code></pre>
  <p>To test whether the server selects the configured cipher suite, I start the client as</p>
  <pre><code>openssl s_client -connect 3.135.190.131:50000 -cert ../client/client_certificate1.pem -key ../client/private_key.pem -CAfile ca_certificate.pem
  </code></pre>
  <p>But when I start connect the client to the server, the server selects: <strong>TLS_AES_256_GCM_SHA384</strong> instead of the configured: <strong>ECDHE-RSA-AES256-GCM-SHA384</strong>
  Also, I checked the trace and the client does send the ECDHE-RSA-AES256-GCM-SHA384 in the cipher suite list.</p>
  <p>Can you suggest what could be wrong on the server side command?</p>