Skip to content

[Support] Update troubleshooting-cloudflare-5xx-errors.mdx #21679

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
wants to merge 1 commit into from
Closed

[Support] Update troubleshooting-cloudflare-5xx-errors.mdx #21679

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
12 changes: 10 additions & 2 deletions ...ort/troubleshooting/cloudflare-errors/troubleshooting-cloudflare-5xx-errors.mdx
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -118,12 +118,13 @@ HTTP error 503 occurs when your origin web server is overloaded.

### Common causes

There are two possible causes identifiable by the error message:
There are different causes identifiable by the error message or the location of the error:

- Error does not contain `cloudflare` or `cloudflare-nginx` in the HTML response body. In this case, the issue is likely from your origin server.
- Error contains `cloudflare` or `cloudflare-nginx` in the HTML response body. In this case, the issue may stem from Cloudflare.
- Error is only visible in the logs or analytics

Additionally, `503` status codes in logs or analytics may result from [unsuccessful prefetches from Speed Brain](/speed/optimization/content/speed-brain/#how-speed-brain-works).
Additionally, `503` status codes in logs or analytics may result from .

### Resolution

Expand All @@ -141,6 +142,13 @@ If the error contains `cloudflare` or `cloudflare-nginx` in the HTML response bo
- The time and timezone of the `503` error occurrence
- The output of `www.example.com/cdn-cgi/trace` from the browser where the `503` error was observed (replace `www.example.com` with your actual domain and hostname)

#### 503 Error only visible in logs and analytics

These errors result from [unsuccessful prefetches from Speed Brain](/speed/optimization/content/speed-brain/#how-speed-brain-works) and can be discarded.
These errors are not visible to visitors of your website.
[Speed Brain](/speed/optimization/content/speed-brain/#enable-and-disable-speed-brain) can be disabled for the zone if needed (this feature cannot be disabled for a specific path).


## Error 520: web server returns an unknown error

This error occurs when the origin server returns an empty, unknown, or unexpected response to Cloudflare.
Expand Down