Why bootdev — CDN configuration

CDN illustration

Why bootdev CDN config

One of BootDev’s website backend feature is CDN auto-deploy. The idea is we deploy the right way of using Amazon Cloudfront (CDN) automatically. You don’t need to investigate and do lots of work in Drupal to make things done.

From our hard earned experience, Drupal CDN configuration summarize as 2

  1. File storage + CDN (Drupal AmazonS3 module + CNAME with Cloudfront)
  2. Directly CDN (Drupal CDN Module)

1. Drupal AmazonS3 module

This module is great. It helps to move Drupal file system on Cloud. The advantage is you don’t need big local storage. But, you will be headache of using this. Some examples are

  • Generating XMLsitemap, the cron job will hang as it is not using local storage
  • new image style, you will need to turn off AmazonS3 module to add new style
  • Features module operations take longer, especially with image field operations
  • Multi-upload / insert image to editor, as the style generation link will be shown at the first time (/system/styles/files/….) will be different when the same style shown second time (CDN url). If you are not notice about it, your image will keep generate and waste lots lots of CPU.
  • Nginx Support, you will need to add AmazonS3 Nginx support (try url /system/stles/files)

For the multi-upload problem, you will need to insert images when u “edit” it rather than create. But, it will complain by your content editor. Another solution is running a quick fix database script to change the url in text body after image generated.

For the others, share some code snap as below, you can put this in your Drupal settings.php or config in admin page. Of coz, you will need to set your AWS right way like setting right S3 bucket as the Cloudfront origin, map to Route53 CNAME of your domain and put it on Cloudfront CNAME. That’s why you need bootdev if you are not understand what I’m talking about.

$conf[‘aws_key’] = ‘your key’;
$conf[‘aws_secret’] = ‘your secret’;
$conf[‘amazons3_bucket’] = ‘your bucket for AmazonS3 module’;
$conf[‘amazons3_cache’] = ‘1’;
$conf[‘amazons3_cloudfront’] = ‘1’;
$conf[‘amazons3_cname’] = ‘1’;
$conf[‘amazons3_domains’] = ‘cdn1.xxx.com
your mutiple CNAME, to increase frontend performance.
You will need this patch https://www.drupal.org/node/2044307#comment-9384777 ‘;

For support nginx, so that image styles can be generated, you will need this

  # Catch image styles for D7.
location ~ ^/sites/.*/files/ {
try_files $uri @rewrite;

# Catch image styles for AmazonS3 D7.
location ~ ^/system/files/styles/ {
try_files $uri @rewrite;

2. Drupal CDN module

OK, now images are served. But what about the css/js/other static resources ? You will need CDN module.

You will need to config AWS to pull your data which we are not going to explain here howto. After that, you can have your CDN module to alter your site url, so that for examples: .css .js .xx will alter to CDN url.

Here is some basic config which u can put into your Drupal settings.php

$conf[‘cdn_basic_mapping’] = ‘http://d2fqrtkrfnbzdb.cloudfront.net| .css .js
http://yourlocalsite.com|.ttf .woff .svg .eot’;
$conf[‘cdn_mode’] = ‘basic’;

//CDN conf (Improve frontend performance)
$conf[‘cdn_farfuture_status’] = ‘1’;

d2fqrtkrfnbzdb.cloudfront.net is your CDN url, you can have other CNAME. You will see i put yourlocalsite.com as a CDN, which is not a good way. Why we are doing this is, we want to keep the webfront files serve as local. So that it won’t have CORS problem. Otherwise your font won’t work. Another approach is uploading your font to S3 manually and then manually set S3 CORS header and then set it as ClountFront origin. But, it make things complex and the font will leave the git repo management, which harder to deploy. So, we suggest to serve it locally, if you do not a very very large site.

You can also add .png next to .css / .js to serve your logo/icons or other resources. And Far future conf help to expire your resource at browser later and suggested to turn on.

To support far future, you will need below in nginx config, so that your CDN can curl the far future path. Reference: https://www.drupal.org/node/2380397

### CDN Far Future expiration support.
location ^~ /cdn/farfuture/ {
tcp_nodelay   off;
access_log    off;
log_not_found off;
etag          off;
gzip_http_version 1.0;
if_modified_since exact;
location ~* ^/cdn/farfuture/.+\.(?:css|js|jpe?g|gif|png|ico|bmp|svg|swf|pdf|docx?|xlsx?|pptx?|tiff?|txt|rtf|class|otf|ttf|woff|eot|less)$ {
expires max;
add_header X-Header “CDN Far Future Generator 1.0”;
add_header Cache-Control “no-transform, public”;
add_header Last-Modified “Wed, 20 Jan 1988 04:20:42 GMT”;
rewrite ^/cdn/farfuture/[^/]+/[^/]+/(.+)$ /$1 break;
try_files $uri @nobots;
location ~* ^/cdn/farfuture/ {
expires epoch;
add_header X-Header “CDN Far Future Generator 1.1”;
add_header Cache-Control “private, must-revalidate, proxy-revalidate”;
rewrite ^/cdn/farfuture/[^/]+/[^/]+/(.+)$ /$1 break;
try_files $uri @nobots;
try_files $uri @nobots;

After you do all above, you can have CDN run smoothly and also cloud storage + CDN for Drupal 🙂 Or use bootdev, one click, all set.


Why cloudfront / CDN ?

  1. Faster your content to audience
  2. Lower your AWS network traffic cost
  3. Available world wide
  4. Lower your Server CPU/Memory as requests share to CDN

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