Setting up CDN for 1C-Bitrix: how to speed up the site and reduce server load
We often encounter a situation: an online store on Bitrix is slow in the regions, and the server is overwhelmed during peak loads. CDN (Content Delivery Network) solves both problems — it offloads the server from serving static content and reduces load time for remote users.
For example, for a store with an audience across Russia, the difference between Moscow and Vladivostok without CDN is 150–200 ms just for DNS and TCP. With a CDN Point of Presence in Vladivostok, static content is served in 5–15 ms.
Over 10 years, we have set up CDN for 50+ Bitrix projects — we share our experience. Without proper CDN configuration, even a powerful server won't help — the bottleneck remains at the network level.
Main problems that CDN solves
- High latency for geographically remote users. Without CDN, requests go to a single server, which is critical for regions of Russia and the CIS.
- Server overload from static content. According to our measurements, up to 80% of traffic on a typical store is images, CSS, and JS. Serving them via CDN reduces the load on the CPU and network of the main server by 50–70%.
- Suboptimal caching. Typical Bitrix settings do not always correctly set Cache-Control for static content, which leads to extra requests.
How to choose a CDN provider for Bitrix?
When choosing a CDN, consider coverage, price, and integration. Here is a comparison of popular providers for Bitrix projects:
| Provider | Coverage in Russia | Free plan | Purge API | SSL/TLS |
|---|---|---|---|---|
| Cloudflare | Limited (Moscow, St. Petersburg) | Yes (up to 100 GB) | Yes | Automatic |
| G-Core Labs | Broad (10+ PoPs in Russia) | No (trial period) | Yes | Let's Encrypt |
| Selectel CDN | Good (Moscow, St. Petersburg, Novosibirsk) | No | Yes | Own CA |
| KeyCDN | Europe, Asia | No | Yes | Let's Encrypt |
For the Russian segment, G-Core Labs is optimal — low latency in all regions. Cloudflare is suitable for a start, but the free plan caches only static content, and the provider may filter traffic. Read more about CDN technology in external sources. Source: Wikipedia
Why doesn't CDN cache dynamic pages?
Dynamic pages (catalog, cart) with PHP processing are dangerous to cache on CDN — users would see other people's data. Therefore, only static resources are moved to CDN: files from /bitrix/cache/css/, /bitrix/js/, /upload/, fonts, icons.
The built-in module bitrix.cdn automatically rewrites the URLs of these resources to the CDN domain. If the module is not used — configure nginx sub_filter or a provider-side rule.
How to set up CDN for Bitrix: step-by-step instructions
- Choosing a provider and registration. Decide on a provider (we recommend G-Core Labs for Russia), create an account, get a CNAME or PTR record.
- DNS and SSL setup. Point a CNAME to the CDN domain (e.g.,
cdn.mysite.ru). The provider will automatically issue an SSL certificate. - Configuring the CDN module in Bitrix. In the admin panel:
Settings → Performance → CDN. Specify the CDN domain and path masks (/upload/*,/bitrix/cache/*). In the "Business" version and above, the module is built-in. - Verification and cache invalidation. After setup, verify that static content is served from CDN (via
curl -I). Set up automatic purge when templates are updated — use the provider's API via theOnAfterUpdateStaticFilesevent. - Speed monitoring. Compare load time before and after via PageSpeed or WebPageTest. Typical TTFB reduction for static content — from 200 ms to 20 ms.
Cache policy and invalidation
Correct Cache-Control for Bitrix static content: files with a hash in the name (generated by Bitrix during compression) — max-age=31536000, immutable. Files without a hash (style.css, script.js) — no more than a day with must-revalidate.
Cache invalidation when updating a template: use the provider's API to purge by URL or masks. This is automated via a deployment hook or the Bitrix event OnAfterUpdateStaticFiles.
Here is a table of recommended Cache-Control values for different file types:
| File type | Example path | Cache-Control | Comment |
|---|---|---|---|
| Hashed CSS/JS | /bitrix/cache/css/*.css? |
max-age=31536000, immutable |
Hash changes on update |
| Unhashed | /bitrix/js/main/core.js |
max-age=86400, must-revalidate |
Need to verify relevance |
| Images | /upload/medialibrary/*.jpg |
max-age=86400 |
Resource-intensive file type |
What is included in turnkey CDN setup
- Audit of the current architecture and identification of bottlenecks.
- Provider selection taking into account the audience geography.
- DNS, SSL setup (automatic issuance).
- Integration with the
bitrix.cdnmodule or nginxsub_filter. - Cache policy configuration:
Cache-Controlwithmax-ageandimmutablefor hashed files. - Automation of cache invalidation via the provider's API.
- Performance testing (A/B test before/after).
- Documentation and training for your team.
Case study from our practice
Our client is an online store with an audience in Russia and Kazakhstan. After connecting CDN (G-Core Labs), page load time for users from Kazakhstan decreased from 3.8 s to 1.4 s — solely due to static content. The PHP part was not changed.
Traffic savings on the main server amounted to 65%. This confirms that a properly configured CDN speeds up the site by 2.7 times without backend modifications.
Timelines and cost
Setting up CDN for Bitrix takes from 1 to 3 days depending on complexity (provider selection, DNS setup, module configuration, testing). Cost is calculated individually — it depends on the number of caching zones developed and automation.
Contact us — we will study your project and prepare an estimate. Get a consultation: write to us in chat or leave a request — we will help with CDN selection and turnkey setup.