API JSON can not connect to website after using cloudflare

Dear

I have problem in connection my API [json format] after using Cloudflare for my website

I have 2 server,…server A and server B
server A => without Cloudflare
server B => using Cloudflare

before using Cloudflare,…the API between server A and server B still working,…
after using cloudlfare,…the API can’t working

I already add the IP Address of server A to whitelist in Cloudflare
but sometime connected,…sometime can’t connect
maybe the problem in “Challenge Passage”
I don’t know how to solve this problem,
please any help

thank you in advance

Best Regards

Johanes

What port(s) you are using for your API?

We are using HTTPS (443)
for the first hit -> it often failed
but for the second or the third hit => sometime succes, sometime failed to connect
anyone can help me,…?
thankyou in advance

Best Regards

Johanes

You need to debug the application and check server response. By comparison of response when call fails and succeeds, you get enough information for the next step.

Was this issue resolved? I’m having the same problem.

I also experienced the same thing. My setup API server in nodeJS, proxied using NGINX behind cloudflare. It has intermittent problem only if I hit it with domain. I solved it by put changing my dns from proxied into dns only.

Apparently cloudflare caches everything, which is not good for an API server. Happy Coding.