didiao 我也遇到过同样的问题，你估计也是nginx直接配置反代，忘记在IP后面加端口了，SSL转发也要在IP后面:443这样配置

这是七层反代配置文件原文（为保隐私，部分配置已经被替代，如域名或upstream的IP地址）：

upstream appnode_proxy_backend_of_site_abc.com {

server 1.1.1.1:80 weight=1 max_fails=3 fail_timeout=5s;
server 1.1.1.2:80 weight=1 max_fails=3 fail_timeout=5s backup down;
server 1.1.1.3:80 weight=1 max_fails=0 fail_timeout=5s backup down;
server 1.1.1.4:80 weight=1 max_fails=0 fail_timeout=5s backup down;
keepalive 1;

}

server {

listen 80;

listen 443 ssl http2;
server_name abc.com;
server_name www.abc.com;
ssl_certificate /data/rp-hkg/sites/abc.com/ssl/site.crt;
ssl_certificate_key /data/rp-hkg/sites/abc.com/ssl/site.key;
ssl_prefer_server_ciphers on;
ssl_ciphers ECDHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-SHA384:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES256-SHA:ECDHE-RSA-AES128-SHA:DHE-RSA-AES256-SHA256:DHE-RSA-AES128-SHA256:DHE-RSA-AES256-SHA:DHE-RSA-AES128-SHA:ECDHE-RSA-DES-CBC3-SHA:EDH-RSA-DES-CBC3-SHA:AES256-GCM-SHA384:AES128-GCM-SHA256:AES256-SHA256:AES128-SHA256:AES256-SHA:AES128-SHA:DES-CBC3-SHA:HIGH:!aNULL:!eNULL:!EXPORT:!CAMELLIA:!DES:!MD5:!PSK:!RC4;
ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
ssl_session_cache shared:SSL:5m;
ssl_session_timeout 5m;
keepalive_timeout 75s;
keepalive_requests 100;
access_log /data/rp-hkg/sites/abc.com/log/nginx/access.log;
error_log /data/rp-hkg/sites/abc.com/log/nginx/error.log;
gzip on;
gzip_comp_level 6;
gzip_min_length 1k;
gzip_types text/plain text/css text/xml text/javascript text/x-component application/json application/javascript application/x-javascript application/xml application/xhtml+xml application/rss+xml application/atom+xml application/x-font-ttf application/vnd.ms-fontobject image/svg+xml image/x-icon font/opentype;

location / {

proxy_pass $scheme://appnode_proxy_backend_of_site_abc.com$request_uri;
proxy_set_header 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_set_header X-Nginx-Proxy true;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection $connection_upgrade;
client_max_body_size 1m;
}
}

在这个配置文件下，请求HTTPS会报告502，错误日志提示为“No live upstreams”。

四层转发，我配置了两个同名域名文件，分别对应80端口和443端口。

80端口配置文件如下：

upstream appnode_proxy_backend_of_site_abc.com {

server 1.1.1.1:80 weight=1 max_fails=3 fail_timeout=5s;
server 1.1.1.2:80 weight=1 max_fails=3 fail_timeout=5s backup down;
server 1.1.1.3:80 weight=1 max_fails=0 fail_timeout=5s backup down;
server 1.1.1.4:80 weight=1 max_fails=0 fail_timeout=5s backup down;

}

server {

listen 80;
access_log /data/rp-hkg/sites/abc.com/log/nginx/access.log proxy;
proxy_pass appnode_proxy_backend_of_site_abc.com;

}

443端口配置文件如下：

upstream appnode_proxy_backend_of_site_sitessl {

server 1.1.1.1:443 weight=1 max_fails=3 fail_timeout=5s;
server 1.1.1.2:443 weight=1 max_fails=3 fail_timeout=5s;
server 1.1.1.3:443 weight=1 max_fails=3 fail_timeout=5s backup;
server 1.1.1.4:443 weight=1 max_fails=3 fail_timeout=5s backup;

}

server {

listen 443 ssl;
access_log /data/rp-hkg/sites/sitessl/log/nginx/access.log proxy;
proxy_pass appnode_proxy_backend_of_site_sitessl;

}

这种情况下，nginx验证通过，但是nginx进程重启则会报错，提示为端口已存在，但实际通过netstat -anp | grep 80或netstat -anp | grep 443查询时为无结果。

● nginx.service - nginx - high performance web server

Loaded: loaded (/usr/lib/systemd/system/nginx.service; enabled; vendor preset: disabled)

Active: failed (Result: exit-code) since Fri 2019-04-05 06:39:06 CST; 9s ago

Docs: http://nginx.org/en/docs/

Process: 17365 ExecStop=/bin/kill -s TERM $MAINPID (code=exited, status=0/SUCCESS)

Process: 17472 ExecStart=/usr/sbin/nginx -c /etc/nginx/nginx.conf (code=exited, status=1/FAILURE)

Main PID: 5600 (code=exited, status=0/SUCCESS)

Apr 05 06:39:05 rp-hkg nginx[17472]: nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)

Apr 05 06:39:05 rp-hkg nginx[17472]: nginx: [emerg] bind() to 0.0.0.0:443 failed (98: Address already in use)

Apr 05 06:39:05 rp-hkg nginx[17472]: nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)

Apr 05 06:39:06 rp-hkg nginx[17472]: nginx: [emerg] bind() to 0.0.0.0:443 failed (98: Address already in use)

Apr 05 06:39:06 rp-hkg nginx[17472]: nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)

Apr 05 06:39:06 rp-hkg systemd[1]: nginx.service: control process exited, code=exited status=1

Apr 05 06:39:06 rp-hkg nginx[17472]: nginx: [emerg] still could not bind()

Apr 05 06:39:06 rp-hkg systemd[1]: Failed to start nginx - high performance web server.

Apr 05 06:39:06 rp-hkg systemd[1]: Unit nginx.service entered failed state.

Apr 05 06:39:06 rp-hkg systemd[1]: nginx.service failed.