I am planning to move all my static content to a CDN so on my server I only have dynamic content left. I now have Nginx set up as reverse proxy to Apache. The static request that came in where directly delivered by Nginx without having to go to Apache.
In this case Nginx handled a large portion of the request and I can clearly see the necessity of Nginx.
Now that I moved all the static content to another domain, is there still a need to have nginx in front of Apache. Because now all the request are by default dynamic requests and all go to Apache.
Are there any other benefits of having Nginx and Apache running for only dynamic content.
My dynamic content is PHP/MySQL
Edit:
To be clear: I now have Nginx as a reverse proxy. It delivers static and dynamic content. But I am moving my static files to a CDN. Do I then still need Nginx on my domain.
No, you don't need nginx anymore.
Yes you absolutely do need nginx in front of Apache. Apache uses 1 thread or process per connection. Each of these threads occupy memory. If you have a few hundred people visiting your website and you have keepalive enabled, each of these browsers will keep an apache process or thread busy occupying memory on your server.
You can work around this by disabling keepalive on your apache server but this slows down the performance of your website because browsers can't reuse connections.
So instead you use nginx as a reverse proxy with keepalive enabled. It can maintain thousands of connections with a tiny memory footprint (about 8 megs). Because nginx is local to your apache server each request only occupies an apache child or thread for a few microseconds. That means you can serve thousands of people with only a tiny handful of apache processes.
Also nginx's configuration is much more flexible than apache and by having it on the front end it gives you a lot of flexibility.
What I've done for one website is :
- set up nginx as a reverse proxy in front of Apache
- configure it so :
- Requests to PHP pages (i.e. dynamic content) are sent to Apache
- Requests to static files (CSS, JS, ...) are directly served by nginx.
This without having to set up two domains : all is on the same domain.
Basically, what I've done is :
- serve images from nginx, without gzip compression, with caching
- serve js/css (i.e. text files) from nginx, with gzip compression, with caching
- serve some other extensions (pdf, exeutables, ...) form nginx, without compression, without caching
- pass the other requests to Apache
Here's how my nginx's configuration file looks like :
server {
listen 80;
server_name MY_DOMAIN_NAME;
access_log /var/log/nginx/MY_DOMAIN_NAME.access.log;
gzip on;
gzip_comp_level 2;
gzip_proxied any;
gzip_types text/plain text/html text/css text/xml application/xml application/xml+rss application/xml+atom text/javascript application/x-javascript application/javascript;
location ~* ^.+\.(jpg|jpeg|gif|png|ico)$ {
root /home/www/MY_DOMAIN_NAME;
#access_log off;
gzip off;
expires 1d;
}
location ~* ^.+\.(css|js)$ {
root /home/www/MY_DOMAIN_NAME;
#access_log off;
expires 1d;
}
location ~* ^.+\.(pdf|gz|bz2|exe|rar|zip|7z)$ {
root /home/www/MY_DOMAIN_NAME;
gzip off;
}
location / {
proxy_pass http://MY_DOMAIN_NAME:8080;
proxy_redirect off;
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_max_temp_file_size 0;
client_max_body_size 10m;
client_body_buffer_size 128k;
proxy_connect_timeout 90;
proxy_send_timeout 90;
proxy_read_timeout 90;
proxy_buffer_size 4k;
proxy_buffers 4 32k;
proxy_busy_buffers_size 64k;
proxy_temp_file_write_size 64k;
}
}
Now, why do such a thing ?
Well, nginx is supposed to :
- Need less memory
- Be faster
- Be able to handle more connections
So, I suppose it could help on a website with a bit of traffic, to lower the load that's put on Apache.
You can also use nginx to offload SSL processing from the apache instances.
For example, we have one stack configured with nginx->haproxy->pool of apache servers. nginx and haproxy live together on a heartbeat cluster and feed requests into a pool of apache boxes on the backend. We install all the SSL certs on the nginx frontend.
nginx in front is the best solution in case you use Apache 1.3:
nginx can easily serve thousands of conections, but Apache can't