# Nginx maintenance page

**URL:** <https://www.ruby-forum.com/t/nginx-maintenance-page/143145>\
**Category:** NGINX\
**Created:** [July 15, 2008, 5:54pm UTC](https://www.ruby-forum.com/t/nginx-maintenance-page/143145 "2008-07-15T17:54:10Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![arfon](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/f4b2a3/32.png) [@arfon](https://www.ruby-forum.com/u/arfon)\
**Post date:** [July 15, 2008, 5:54pm UTC](https://www.ruby-forum.com/t/nginx-maintenance-page/143145/1 "2008-07-15T17:54:10Z")

</div>

I’m having a little trouble getting the Nginx maintenance pages working  
as I’d like them to.

I have the following rewrite rule in my Nginx config file:

if (-f /software/shared/system/maintenance.html) {  
rewrite ^(.\*)$ /system/maintenance.html last;  
break;  
}

The problem I’m having is that this maintenance page is only showing up  
when the Rails application is still running in the background. If I  
kill the Rails app I get a 502 Bad Gateway error and checking the Nginx  
error log I see that Nginx is asking the mongrels to server the  
maintenance file (but they’re not there as the application isn’t  
running!)

I’ve copied in my full config below.

Any help would be greatly appreciated!

Arfon

#user nobody;  
worker\_processes 5;

pid /software/shared/log/nginx.pid;  
error\_log /software/shared/log/nginx.error.log;

events {  
worker\_connections 1024;  
}

http {  
include /software/shared/config/mime.types;  
default\_type application/octet-stream;

```
log_format main '$remote_addr - $remote_user [$time_local]

```

$request ’  
'"$status" $body\_bytes\_sent “$http\_referer” ’  
‘"$http\_user\_agent" “$http\_x\_forwarded\_for”’;

```
access_log /software/shared/log/nginx.access.log main;
client_body_temp_path /software/shared/nginx/client_temp 1 2;
proxy_temp_path /software/shared/nginx/proxy_temp 1 2;
fastcgi_temp_path /software/shared/nginx/fastcgi_temp 1 2;

sendfile on;
tcp_nopush on;
tcp_nodelay off;

#keepalive_timeout 0;
keepalive_timeout 65;

gzip on;
gzip_http_version 1.0;
gzip_comp_level 2;
gzip_proxied any;
gzip_types text/plain text/html text/css

```

application/x-javascript text/xml application/xml application/xml+rss  
text/javascript;

```
  upstream mongrel {
  server myapp.com:6641;
  server myapp.com:6642;
  server myapp.com:6643;
  server myapp.com:6644;
  server myapp.com:6645;
}
server {
    listen 6640;
    client_max_body_size 50M;
    root /software/shared/system;

    #access_log log/host.access.log main;
    rewrite_log on;

    if (-f /software/shared/system/maintenance.html) {
      rewrite ^(.*)$ /system/maintenance.html last;
      break;

    }

   location / {

      # needed to forward user's IP address to rails
      proxy_set_header X-Real-IP $remote_addr;

      root html;
      index index.html index.htm;

      # needed for HTTPS
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
      proxy_set_header Host $http_host;
      proxy_redirect false;
      proxy_max_temp_file_size 0;

      # If the file exists as a static file serve it directly

```

without  
# running all the other rewite tests on it  
if (-f $request\_filename) {  
break;  
}

```
      # this is the meat of the rails page caching config
      # it adds .html to the end of the url and then checks
      # the filesystem for that file. If it exists, then we
      # rewite the url to have explicit .html on the end
      # and then send it on its way to the next config rule.
      # if there is no file on the fs then it sets all the
      # necessary headers and proxies to our upstream mongrels
      if (-f $request_filename.html) {
        rewrite (.*) $1.html break;
      }

      if (!-f $request_filename) {
        proxy_pass http://mongrel;
        break;
      }
    }

    #error_page 404 /404.html;

    # redirect server error pages to the static page /50x.html
    error_page 500 502 503 504 /50x.html;
    location = /50x.html {
        root html;
    }
}

```

}

---

<div class="post-metadata">

**Author:** ![arfon](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/f4b2a3/32.png) [@arfon](https://www.ruby-forum.com/u/arfon)\
**Post date:** [July 16, 2008, 1:41am UTC](https://www.ruby-forum.com/t/nginx-maintenance-page/143145/2 "2008-07-16T01:41:56Z")

</div>

> If I kill the Rails app I get a 502 Bad Gateway error

Short answer: run /etc/init.d/nginx reload after creating  
/system/maintenance.html (and do it again after removing the maintenance  
file)

It sounds like your Rails processes are serving the maintenance page.  
When your  
Rails processes are down nginx appears to be still trying to proxy the  
request  
to Rails - which results in a 502. That implies that nginx is not  
attempting to  
serve the maintenance.html page at all. This has happened to me in the  
past and  
I found that I needed to reload nginx.conf for it to pick up a newly  
created  
maintenance file.

If that doesn’t work, then compile nginx with debugging enabled  
(./configure  
–with-debug) and add debug\_http to the end of your error\_log  
configuration.  
Then you can watch the rewriting rules in action by tailing your  
error.log.

---

<div class="post-metadata">

**Author:** ![arfon](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/f4b2a3/32.png) [@arfon](https://www.ruby-forum.com/u/arfon)\
**Post date:** [July 17, 2008, 2:23am UTC](https://www.ruby-forum.com/t/nginx-maintenance-page/143145/3 "2008-07-17T02:23:10Z")

</div>

On Jul 15, 2008, at 11:54 AM, Arfon S. wrote:

> I’m having a little trouble getting the Nginx maintenance pages  
> working  
> as I’d like them to.

maintenance pages? is this i feature i missed?

something i could use to replace our own current ones?

can someone point me in the direction of some docs as i cant seem to  
find anything on this?

thanks.

-sean-

---

<div class="post-metadata">

**Author:** ![arfon](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/f4b2a3/32.png) [@arfon](https://www.ruby-forum.com/u/arfon)\
**Post date:** [July 17, 2008, 11:43am UTC](https://www.ruby-forum.com/t/nginx-maintenance-page/143145/4 "2008-07-17T11:43:51Z")

</div>

On Thu, Jul 17, 2008 at 11:34 AM, Thomas [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

> It’s simply a rewrite rule that will deliver the maintenance page (if  
> it exists) to all incoming request. You still need to design your own  
> nicely crafted maintenance page though.

My bad, it is not a rewrite rule! It is a rule (no rewrite) for Nginx  
to look for a maintenance page, and if it exists, it sends it back no  
matter which request is coming in. A rewrite rule is not even needed.

---

<div class="post-metadata">

**Author:** ![arfon](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/f4b2a3/32.png) [@arfon](https://www.ruby-forum.com/u/arfon)\
**Post date:** [July 17, 2008, 3:27pm UTC](https://www.ruby-forum.com/t/nginx-maintenance-page/143145/5 "2008-07-17T15:27:10Z")

</div>

On Jul 17, 2008, at 5:36 AM, Thomas wrote:

> On Thu, Jul 17, 2008 at 11:34 AM, Thomas [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:
> 
> > It’s simply a rewrite rule that will deliver the maintenance page (if  
> > it exists) to all incoming request. You still need to design your own  
> > nicely crafted maintenance page though.
> 
> My bad, it is not a rewrite rule! It is a rule (no rewrite) for Nginx  
> to look for a maintenance page, and if it exists, it sends it back no  
> matter which request is coming in. A rewrite rule is not even needed.

hmm yes, but would that one prevent any images being on the page?  
looks pretty much like ours… in its general idea…

if ( -f $document\_root/.maintenance )  
{  
set $maintenance 1;  
}

if ( $uri ~ ^/maintenance/ )  
{  
set $maintenance 0;  
}

if ( $maintenance )  
{  
rewrite (.\*) /maintenance/index.html last;  
}

if file exists, serve maintenance. ( with bypass for any other files  
in /maintenance ) directory.

---

<div class="post-metadata">

**Author:** ![arfon](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/f4b2a3/32.png) [@arfon](https://www.ruby-forum.com/u/arfon)\
**Post date:** [July 17, 2008, 11:43am UTC](https://www.ruby-forum.com/t/nginx-maintenance-page/143145/6 "2008-07-17T11:43:51Z")

</div>

It’s simply a rewrite rule that will deliver the maintenance page (if  
it exists) to all incoming request. You still need to design your own  
nicely crafted maintenance page though.