CDN sending 504 on certain images RRS feed

  • Question

  • Our team is using Azure CDN for image distribution. Recently we received reports that some images are not showing up on our website. After some investigation, I found that the response from the CDN is HTTP 504. This problem can be replicated on any client (browser). Direct access to those images are ok.

    For example, the following image can be accessed directly


    However, through CDN, it returns 504


    Other images are fine. For example,



    I have tried to purge the CDN, which did not solve the problem. I have also Googled related topics. Most of them have issues with HTTPS certificate. Our server do not have HTTPS on regular page (where these images reside). Moreover, this problem only happens to certain images. I have no clue why this happens.

    If anyone could give me some advice on where to dig into, it would be very appreciated.

    Wednesday, August 17, 2016 1:11 AM

All replies

  • Hey Dennis, the url you mentioned 504s is currently returning 200.


    Can you confirm the issue is still happening?



    Wednesday, August 17, 2016 6:27 PM
  • This is weird. On my network, it is still 504. After testing on some other networks, looks like they are all 200. I will look into the firewall configurations with the IT department.

    Thank you.

    Thursday, August 18, 2016 5:09 PM