Jenkins nginxは、「安全でない」2つのサブドメインを構成します。

ウェブサイトから一つを得たnot secureのですが、なぜそうなのか理解できません。それはnginx設定です。

upstream jenkins-av-server {
  server jenkins.audience-view:8080 fail_timeout=0;
}

server {
  listen 80;
  server_name audience-view.jenkins.example.com;
  return 301 https://$host$request_uri;
}


server {
       listen       443;
       server_name  audience-view.jenkins.example.com;

       ssl                  on;
       ssl_certificate    /etc/nginx/certificates/example.com.crt;
       ssl_certificate_key    /etc/nginx/certificates/example.com.key;

       ssl_protocols  TLSv1.2;
       ssl_ciphers ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:DH+AES:ECDH+3DES:DH+3DES:RSA+AESGCM:RSA+AES:RSA+3DES:!aNULL:!MD5:!DSS;

       ssl_session_cache shared:SSL:128m;
       ssl_session_timeout 10m;

       ssl_prefer_server_ciphers   on;

       access_log      /var/log/nginx/audience-view.jenkins.access.log;
       error_log       /var/log/nginx/audience-view.jenkins.error.log;

  location / {
       proxy_set_header Host $host:$server_port;
       proxy_set_header X-Forwarded-Host $host;
       proxy_set_header X-Real-IP $remote_addr;
       proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
       proxy_set_header X-Forwarded-Proto $scheme;
       proxy_pass          http://jenkins.audience-view:8080;
       proxy_redirect http://jenkins.audience-view:8080 https://audience-view.jenkins.example.com;

       }
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    }