title: nginx proxy pass subpaths not redirected
body: <p>I have the following nginx config:</p>
  
  <pre><code>    location /mail {
             rewrite           ^/mail/(.*) /$1 break;
             proxy_pass https://roundcube-host;
             proxy_connect_timeout 1;
             proxy_set_header X-Real-IP $remote_addr;
             proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
             proxy_set_header Host $http_host;
             proxy_set_header X-Forwarded-Proto https;
      }
  </code></pre>
  
  <p>with:</p>
  
  <pre><code>    upstream roundcube-host {
            server roundcube-ip-address:443;
      }
  </code></pre>
  
  <p>So, I would like to redirect all requests from /mail to a backend roundcube server.</p>
  
  <p>But, only the request which matches <code>/mail</code> is redirected. So, <code>/mail/plugins</code>, etc... are not redirected which means I don't have any CSS or JS, etc. as nginx is trying to find them locally.</p>
  
  <p>How can I have all the paths correctly redirected?</p>
  
  <p>Here is my complete nginx config. The frontend is owncloud.  </p>
  
  <pre><code>upstream phpcgi {
      fair;
      server 127.0.0.1:9000;
      server 127.0.0.1:9001;
      keepalive 5;
  }
  
  upstream roundcube-host {
      server roundcube-ip-address:443;
  }
  
  server {
      listen 443 ssl;
      #server_name cloud.example.com;
  
      ssl_certificate /etc/ssl/certs/owncloud.crt;
      ssl_certificate_key /etc/ssl/private/owncloud.key;
  
      access_log /var/log/nginx/data_access.log;
      error_log /var/log/nginx/data_error.log info;
  
      # Path to the root of your installation
      root /var/www/;
  
      client_max_body_size 10G; # set max upload size
      fastcgi_buffers 64 4K;
  
      rewrite ^/caldav(.*)$ /remote.php/caldav$1 redirect;
      rewrite ^/carddav(.*)$ /remote.php/carddav$1 redirect;
      rewrite ^/webdav(.*)$ /remote.php/webdav$1 redirect;
  
      index index.php;
      error_page 403 = /core/templates/403.php;
      error_page 404 = /core/templates/404.php;
  
      location = /robots.txt {
          allow all;
          log_not_found off;
          access_log off;
      }
  
      location ~ ^/(data|config|\.ht|db_structure\.xml|README) {
              deny all;
      }
  
      location / {
              # The following 2 rules are only needed with webfinger
              rewrite ^/.well-known/host-meta /public.php?service=host-meta last;
              rewrite ^/.well-known/host-meta.json /public.php?service=host-meta-json last;
  
              rewrite ^/.well-known/carddav /remote.php/carddav/ redirect;
              rewrite ^/.well-known/caldav /remote.php/caldav/ redirect;
  
              rewrite ^(/core/doc/[^\/]+/)$ $1/index.html;
  
              try_files $uri $uri/ index.php;
      }
  
      location ~ ^(.+?\.php)(/.*)?$ {
              try_files $1 = 404;
  
              include fastcgi_params;
              fastcgi_param SCRIPT_FILENAME $document_root$1;
              fastcgi_param PATH_INFO $2;
              fastcgi_param HTTPS on;
              fastcgi_pass phpcgi;
              # Or use unix-socket with 'fastcgi_pass unix:/var/run/php5-fpm.sock;'
              fastcgi_param MOD_X_ACCEL_REDIRECT_ENABLED on;
      }
  
      # Optional: set long EXPIRES header on static assets
      location ~* ^.+\.(jpg|jpeg|gif|bmp|ico|png|css|js|swf)$ {
              expires 30d;
              # Optional: Don't log access to assets
              access_log off;
      }
  
      # Change the path according to the data directory
      location ~ ^/var/data {
              internal;
              root /;
      }
  
      location ~ ^/tmp/oc-noclean/.+$ {
              internal;
              root /;
      }
  
      location ~ ^/mail(.*)$ {
             rewrite           ^/mail/(.*) /$1 break;
             proxy_pass https://roundcube-host;
             proxy_connect_timeout 1;
             proxy_set_header        Host              $http_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 $https;
      }
  }
  </code></pre>