HAProxy load balancer: Peer's Certificate issuer is not recognized
<p>I just setup a load balancer with HAProxy 1.5.2, and the HTTPS frontend work incorrectly.</p>

<p>I use curl to make an request to my server as follow:
<em>curl <a href="https://haproxy.example.com" rel="nofollow">https://haproxy.example.com</a></em>
The output as follows:</p>

<blockquote>
  <p>curl: (60) Peer's Certificate issuer is not recognized.<br />
  More details here: <a href="http://curl.haxx.se/docs/sslcerts.html" rel="nofollow">http://curl.haxx.se/docs/sslcerts.html</a><br />
  curl performs SSL certificate verification by default, using a "bundle"<br />
   of Certificate Authority (CA) public keys (CA certs). If the default<br />
   bundle file isn't adequate, you can specify an alternate file<br />
   using the --cacert option.<br />
  If this HTTPS server uses a certificate signed by a CA represented in<br />
   the bundle, the certificate verification probably failed due to a<br />
   problem with the certificate (it might be expired, or the name might<br />
   not match the domain name in the URL).<br />
  If you'd like to turn off curl's verification of the certificate, use<br />
   the -k (or --insecure) option.<br /></p>
</blockquote>

<p>The following are the configuration:</p>

<blockquote>
  <p>frontend https-in
   <strong>bind *:443 ssl crt /var/crt/mycrt.pem ca-file /var/crt/myca.crt</strong><br />
   reqadd X-Forwarded-Proto:\ https<br />
   default_backend https-in-443</p>
</blockquote>

<p>The <em>/var/crt/myca.crt</em> are the CA bundle file.</p>

<p>Anybody can help on this issue? thanks a lot.</p>