Nginx反向代理不适用于动态proxy_pass

Question

我正在尝试使用nginx反向代理来代理AWS API，并遇到一个问题，即如果我静态定义上游服务器，它会完美运行，但是如果我尝试动态生成它，则会引发502 Bad Gateway错误。 我不确定如何解决此问题。

/etc/nginx/nginx.conf

user www-data;
worker_processes auto;
pid /run/nginx.pid;

events {
        worker_connections 768;
        # multi_accept on;
}

http {

        ##
        # Basic Settings
        ##

        sendfile on;
        tcp_nopush on;
        tcp_nodelay on;
        keepalive_timeout 65;
        types_hash_max_size 2048;

        include /etc/nginx/mime.types;
        default_type application/octet-stream;

        ##
        # SSL Settings
        ##

        ssl_protocols TLSv1 TLSv1.1 TLSv1.2; # Dropping SSLv3, ref: POODLE
        ssl_prefer_server_ciphers on;

        ##
        # Logging Settings
        ##

        access_log /var/log/nginx/access.log;
        error_log /var/log/nginx/error.log;

        ##
        # Gzip Settings
        ##

        gzip on;
        gzip_disable "msie6";

        ##
        # Logging
        ##

        log_format upstreamlog '[$time_local] $host $remote_addr - $remote_user - $server_name to: $upstream_addr ($upstream_http_name): $request upstream_response_time $upstream_response_time msec $msec request_time $request_time';

        ##
        # Virtual Host Configs
        ##

        include /etc/nginx/conf.d/*.conf;
        include /etc/nginx/sites-enabled/*;
}

/ etc / nginx / sites-enabled / default

server {
        listen 80;

        server_name (.*)\.(.*)\.(.*)\.colinaws\.com (.*)\.(.*)\.colinaws\.com (.*)\.colinaws\.com;

        access_log /var/log/nginx/proxy.log upstreamlog;

        location / {
                if ($host ~* (.*)\.colinaws\.com) {
                        proxy_pass http://$1.amazonaws.com;
                }
                if ($host ~* (.*)\.(.*)\.colinaws\.com) {
                        proxy_pass http://$1.$2.amazonaws.com;
                }
                if ($host ~* (.*)\.(.*)\.(.*)\.colinaws\.com) {
                        proxy_pass http://$1.$2.amazonaws.com;
                }
                proxy_set_header Host $host;
                proxy_pass_header Authorization;
                proxy_pass_header X-Amz-Target;
                proxy_pass_header X-Amz-Date;
                proxy_pass_header User-Agent;
                proxy_pass_header Content-Type;
                proxy_pass_header Content-Length;
                proxy_pass_header Accept-Encoding;
        }
}

在上述配置中，它不起作用，但是如果我继续将proxy_pass静态定义为AWS终端节点（例如， http://dynamodb.us-west-2.amazonaws.com ），则它可以正常工作。

Answer 1

这里的问题是没有将proxy_pass设置为独立变量，也没有设置resolver标志。 这两项的共同作用迫使nginx每次传递都要重新解析URL，而不是在开始时就缓存IP地址。 我的最终（稳定）配置如下所示：

server {
        # Listen on port 80, this will be updated to port 443 once ssl is enabled
        listen 80;

        # Server names should map to incoming requests so we can regex process out the service and
        # region later
        server_name (.*)\.(.*)\.(.*)\.colinaws\.com (.*)\.(.*)\.colinaws\.com;

        # Log the incoming information for debug purposes. The formatter 'upstreamlog' can be found in
        # the config root at /etc/nginx/nginx.conf
        #access_log /var/log/nginx/proxy.log upstreamlog;

        # Need to have a DNS server to resolve the FQDNs provided to proxy_pass
        resolver 8.8.8.8;

        # Parse the incoming FQDN and determine the upstream server
        if ($host ~* (.*)\.(.*)\.colinaws\.com) {
                set $upstream http://$1.amazonaws.com;
        }
        if ($host ~* (.*)\.(.*)\.(.*)\.colinaws\.com) {
                set $upstream http://$1.$2.amazonaws.com;
        }

        # Proxy the request upstream
        location / {
                proxy_pass $upstream;
                proxy_set_header Host $host;
                proxy_pass_header Authorization;
                proxy_pass_header X-Amz-Target;
                proxy_pass_header X-Amz-Date;
                proxy_pass_header User-Agent;
                proxy_pass_header Content-Type;
                proxy_pass_header Content-Length;
                proxy_pass_header Accept-Encoding;
        }
}

Answer 2

您需要使用

server {
        listen 80;

        server_name (.*)\.(.*)\.(.*)\.colinaws\.com (.*)\.(.*)\.colinaws\.com (.*)\.colinaws\.com;

        access_log /var/log/nginx/proxy.log upstreamlog;

        location / {
                if ($host ~* (.*)\.colinaws\.com) {
                        proxy_pass http://$1.amazonaws.com$request_uri$is_args$args;
                }
                if ($host ~* (.*)\.(.*)\.colinaws\.com) {
                        proxy_pass http://$1.$2.amazonaws.com$request_uri$is_args$args;
                }
                if ($host ~* (.*)\.(.*)\.(.*)\.colinaws\.com) {
                        proxy_pass http://$1.$2.amazonaws.com$request_uri$is_args$args;
                }
                proxy_set_header Host $host;
                proxy_pass_header Authorization;
                proxy_pass_header X-Amz-Target;
                proxy_pass_header X-Amz-Date;
                proxy_pass_header User-Agent;
                proxy_pass_header Content-Type;
                proxy_pass_header Content-Length;
                proxy_pass_header Accept-Encoding;
        }
}

在proxy_pass使用变量时，您还需要提供完整的uri和args