About Cloudflare 502 error.

[hatta]

We sometimes get 502 errors in our applications.
To investigate the cause, we tested using a simple application.

Test environment

• Application: GitHub - nio-p/express-hello-world: Express Hello World Example on Render https://render.com
• Spec: Free

The test application executes the following code for each access and returns html.
"console.log(“HELLO: " + new Date());”

After applying a temporary small access load (2-3 requests per second) for about 1 minute, the following screen was displayed.

The server-side log then displayed the following output.

The situation at this time was as follows

1. 502 returned by Cloudflare between 15:15:38 and 15:15:50
2. the Web Server hosted by Render is not down

Even the production application we normally use sometimes returns 502 errors despite small concurrent accesses.

Is this something that is out of Render’s or our control?

Any feedback would be appreciated.

[John_B]

Hi there,
Unfortunately as this is from more than 7 days ago we’re not able to query our CloudFlare logs beyond that - if you’re experiencing this still and provide us with new rayID we can certainly dig into it more,

John B

[hatta]

Hi,

Thank you for reply.

Please check following information about Cloudflare 502 error.

alt-svc: h3=":443"; ma=86400, h3-29=":443"; ma=86400
cf-cache-status: DYNAMIC
cf-ray: 73b975227c4ef8eb-NRT
content-type: text/plain; charset=utf-8
date: Tue, 16 Aug 2022 10:24:00 GMT
expect-ct: max-age=604800, report-uri="https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct"
server: cloudflare
vary: Accept-Encoding
x-content-type-options: nosniff
x-envoy-upstream-service-time: 2386