Website Error 504 Gateway time-out While Using Proxy Mode CloudFlare

[linux4]

What is the name of the domain?

https://tools.anu.biz.id/

What is the error number?

504

What is the error message?

Gateway time-out Host Error

What is the issue you’re encountering

When proxy mode is enabled on the DNS record, the website or domain becomes inaccessible and displays a 504 Gateway Timeout (Host Error) message. However, when proxy mode is disabled (DNS only), the website can be accessed normally. We have another node, and when we enable proxy mode on that node, we do not encounter the same issue.

What steps have you taken to resolve the issue?

Check list ip cloudflare is getting allowlisted in our firewall.

What are the steps to reproduce the issue?

Enable proxy mode on the DNS record

Screenshot of the error

[neiljay]

@linux4

When proxy mode is enabled on the DNS record, the website or domain becomes inaccessible and displays a 504 Gateway Timeout (Host Error) message.

The most common error takes place at the root: your origin server. You’d need to list out what’s causing error. Here’s the doc for resolution:

Error 502 or 504

Apart from that, I see the mentioned sub: https://tools.anu.biz.id/ is not throwing that error right now.

Request URL
https://tools.anu.biz.id/
Request Method
GET
Status Code
200 OK
Remote Address
104.21.56.231:443
Referrer Policy
strict-origin-when-cross-origin
alt-svc
h3=":443"; ma=86400
cf-cache-status
DYNAMIC
cf-ray
95237bd67db8da11-MRS
content-encoding
zstd
content-type
text/html
date
Thu, 19 Jun 2025 13:48:23 GMT
last-modified
Thu, 19 Jun 2025 10:41:48 GMT
nel
{"success_fraction":0,"report_to":"cf-nel","max_age":604800}
report-to
{"endpoints":[{"url":"https:\/\/a.nel.cloudflare.com\/report\/v4?s=sbkKHUHX4TwOE8kWJ8tenrGcxurK77ybE8aMaEWRZxsSxS1mdlUpJiMUY5yy3s%2BlosLz%2BGjboEGuMi2VJtW6QvWhKLAoPM3me4%2B1nf%2BMwZ01QzIgxJwmGKOhOYyT2xQWjn0h"}],"group":"cf-nel","max_age":604800}
server
cloudflare
server-timing
cfCacheStatus;desc="DYNAMIC"
server-timing
cfOrigin;dur=158,cfEdge;dur=9

I see status code: 200 and is accessible:

[linux4]

Thanks for your assistance @neiljay

The issue was solved without any change from us. However, at the time we opened this ticket, Cloudflare had announced maintenance on their Jakarta server.