I’m trying to renew the certificates of my server using certbot standalone plugin (https://certbot.eff.org/docs/using.html#standalone). I’m using a pretty basic setup with only a single machine behind Cloudflare proxy.
When I disable the Cloudflare proxy the challenge is successful and the certificates are renewed. Otherwise this is the kind of errors i get (domain obfuscated):
Domain: example.com Type: unauthorized Detail: Invalid response from https://u15225622.ct.sendgrid.net/ls/click?upn=*random code here* [2607:4701:3027::6g1c:11bd]: "<!DOCTYPE html>\n<!--[if lt IE 7]> <html class=\"no-js ie6 oldie\" lang=\"en-US\"> <![endif]-->\n<!--[if IE 7]> <html class=\"no-js "
This is strange.
Do you have any suggestion?