Using brotli on Azure CDN

Question

Hi is it possible to prefer brotli over gzip on Azure CDN if the browser supports it?

Request header says:
accept-encoding: gzip, deflate, br

but the response header:
content-encoding: gzip

(I am on Chrome Dev on Ubuntu)
According to the docs, https://learn.microsoft.com/en-us/azure/cdn/cdn-improve-performance#compression-rules brotli is already the preferred compression, but I still get a response with gzip compressing.

Answer 1

Hi there, I am still experiencing this problem, how does one change which Azure CDN product is used? I cannot seem to find its settings in the Azure Portal

Answer 2

This behavior will differ depending upon which Azure CDN product you are using. This is a known issue with the Verizon SKUs, but should work fine with the Standard Microsoft offering when requesting brotil.

Answer 3

Hello,
I am using Azure CDN Premium from Verizon

My origin for static file is Azure storage account / blob files.
On static storage, i do have normal / uncompressed files, gzip files and brotli files.
(does are generated automatically during dotnet 5 build for blazor wasm)

Anyhow, I understand that Azure CDN does not support to change on-the-fly compresion models, however i need help to setup static redirection to brotli files? (probably using rules engine v4) based on header request.

I have checked documentation:
https://learn.microsoft.com/en-us/azure/cdn/cdn-improve-performance

• but it is unclear for scenario/setup/question

Others have the same issue / situation / question:
https://stackoverflow.com/questions/58087482/compression-behavior-in-verizon-cdn-in-azure
https://github.com/MicrosoftDocs/azure-docs/issues/52449
https://social.msdn.microsoft.com/Forums/en-US/09811055-574b-45d1-8843-597fd5e86b04/not-getting-brotli-compression-from-azure-cdn?forum=azurecdn