Azure Application Gateway
An Azure service that provides a platform-managed, scalable, and highly available application delivery controller as a service.
1,063 questions
How to fix a recurring 502 bad gateway error
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METAIS BASTIEN
0
Reputation points
We haven't touched our DNS setup for ages.
Still, within the last few weeks, Cloudflare returns sometimes a Cloudflare-branded HTTP 502 error, which means our Azure web server responds with a standard HTTP 502 bad gateway error.
Do you know what the cause could be?
{count} votes
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KapilAnanth-MSFT 45,111 Reputation points Microsoft Employee2024-04-01T06:12:55.7733333+00:00 Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.
Can you please elaborate your environment and architecture.
- I take it that the third party service, Cloudflare provides some sort of DNS + Reverse Proxy to an Azure service
- I also see you have used "Azure Application Gateway" tag
- May I know what exactly is in the backend of this Cloudflare Proxy? Is it an Application gateway or some other Azure service? (as you have mentioned "Azure web server")
- If this is an App gateway, I would suggest you bypass the Proxy and directly access the App Gw and confirm if you are still getting 502?
- Also,
1.Can you let us know how exactly are you confirming the backend Azure service is the one giving 502 and not the Proxy itself?
2.It is quite possible that the Cloudlfare Proxy is giving a 502 but in fact, the backend Azure service is healthy.
Cheers,
Kapil
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