[Help] Getting 503 when using CF

I’ve website hosted at xxx.yyy.zzz.aaa with this topology user --> nginx reverse proxy --> apache httpd.

When I using namecheap, sub.mydomain.tld A xxx.yyy.zzz.aaa my website is working fine. But when I using cloudflare and make anothersub.mydomain.tld A xxx.yyy.zzz.aaa I got 503 from my website. Any clue?

thanks

Is the error page Cloudflare branded?
Also please set your nginx log leel to ‘debug’ and check it.

server {
    #other config
    error_log    /var/logs/nginx/example.com.error.log debug;
    #other config
}

503 is shown under the following circumstances

  • 503 is returned by yoir origin, likely misconfigured nginx
  • Under Attack mode is active
  • Always online was triggered.

A Cloudflare branded 503 means you are hitting a connection limit in a Cloudflare datacenter. Please contact Cloudflare support with the following information:

  • Your domain
  • The output of example.com/cdn-cgi/trace from your browser (replace example.com with your actual site).
  • If you are seeing a traffic surge or attack against your site, please let us know if you are seeing this in your logs.