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Check CDN operation
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Check CDN operation

If there are errors or slow download speeds of content via CDN, check:

Check balance⁠

  1. In the Control Panel, on the top menu, click Products and select CDN.
  2. Look at the account balance in the upper right corner and the status of the CDN resource. If the balance is negative and the CDN resource is in DOWN status, the CDN resource has been disconnected for non-payment.
  3. To enable the CDN resource, top up the balance with the amount owed, then enable the resource.

Check CDN resource⁠

The check will show the status of the CDN resource, the correctness of the CNAME record and the availability of the file from the content source and CDN server.

  1. In the Control Panel, click Products in the top menu and select CDN. In the CDN resource line, view the status. If the resource is in ERROR status or is hung in one of the statuses , create a ticket.

  2. Open the file on the content source using a link like example.com/images/image.png.If the file does not load, the problem is on the side of your site.

  3. Open the file through the default domain using a link of the form *.selcdn.net/images/image.png.The default domain can be viewed in the control panel: in the top menu, click Products → CDN → Resource page → General tab .If the file does not load, check the Host header.

  4. Open the file through the personal domain using a link like cdn.example.com/images/image.png.The personal domain can be viewed in the control panel: in the top menu, click Products → CDN → Resource page → General tab .If the file does not load, check that the domain resource record is correct.

Check content loading speed⁠

The first access to the content source takes longer to download the file than subsequent accesses when the file is distributed from the cache.

  1. Make sure the device you will be checking from has VPN or proxies turned off — they can slow down download speeds.

  2. Check the download speed on the content source:

    2.1 Open the file on the content source.

    2.2 Look at the file download speed, to do this, open developer tools in the browser → Network tab → look at the value in the Time column .

  3. Upload the file to the CDN cache, to do this open the file on the domain that is used to distribute content via CDN.Domains can be viewed in the control panel: in the top menu click Products → CDN → share page → Share tab.

  4. Check the download speed from the CDN cache:

    4.1 Re-open the same file you opened in step 3 on the CDN domain.

    4.2 Look at the speed of file download, to do this, open developer tools in the browser → Network tab → look at the value in the Time column .

  5. Compare the download speed of the file from the source and from the CDN cache. If the CDN download speed is higher or equal to the source download speed, the CDN is working correctly.If the CDN download speed is lower, leave a diagnostic request.

Leave a request for diagnostics⁠

  1. Record the HTTP session with a demonstration of the CDN error in HAR file format.Learn more about recording a HAR file for Edge, Firefox, or Chrome in the How to Get Google Admin Toolbox Portal HAR File instructions.

  2. Create a ticket with a request for diagnostics. In the ticket specify:

    • CDN resource name;
    • a link to a file on the domain that is used to distribute content via CDN;
    • HAR file that you created in step 1;
    • mass of requests with the problem and the location of users who have the problem.