解决Nginx升级到1.15.x报SSL警告

作为一个习惯追新的人，最近把nginx升级到了1.15.2，修改站点配置并重新加载配置文件时，发现报警告。
虽然不影响正常，也不是处女座，但还是看不顺眼，经过一番百度 Google，终于找到原因和解决方法！

报错内容

nginx: [warn] the "ssl" directive is deprecated, use the "listen ... ssl" directive instead in /usr/local/nginx/conf/vhost/test.ll00.cn:24

原因

新版本不推荐使用ssl指令，所以会发出一段警告。使用listen 443 ssl;代替

解决方法

在配置文件里，找到ssl on;，将其注释掉

# ssl on;

然后修改监听端口处的配置后面加上ssl

listen 443 ssl;

相关Nginx更新日志：

Changes with nginx 1.15.0                                        05 Jun 2018

    *) Change: the "ssl" directive is deprecated; the "ssl" parameter of the
       "listen" directive should be used instead.

    *) Change: now nginx detects missing SSL certificates during
       configuration testing when using the "ssl" parameter of the "listen"
       directive.

    *) Feature: now the stream module can handle multiple incoming UDP
       datagrams from a client within a single session.

    *) Bugfix: it was possible to specify an incorrect response code in the
       "proxy_cache_valid" directive.

    *) Bugfix: nginx could not be built by gcc 8.1.

    *) Bugfix: logging to syslog stopped on local IP address changes.

    *) Bugfix: nginx could not be built by clang with CUDA SDK installed;
       the bug had appeared in 1.13.8.

    *) Bugfix: "getsockopt(TCP_FASTOPEN) ... failed" messages might appear
       in logs during binary upgrade when using unix domain listen sockets
       on FreeBSD.

    *) Bugfix: nginx could not be built on Fedora 28 Linux.

    *) Bugfix: request processing rate might exceed configured rate when
       using the "limit_req" directive.

    *) Bugfix: in handling of client addresses when using unix domain listen
       sockets to work with datagrams on Linux.

    *) Bugfix: in memory allocation error handling.