I am using the acme client to generate certificates for the customers hosted on our server. It all works fine for all domain except one.
./acme-client.phar issue --server letsencrypt --storage certificates --domains zorbas-tegernsee.bayern,www.zorbas-tegernsee.bayern --path …/public:…/public --bits 4096
This runs into an invalid challenge. The server is configured correctly, the first check of the tool from the own webserver is delivered with 200. In our access logs I normally see 2 requests for a certificate issue. The first one is the check from of the acme client, the second one from the let’s encrypt server. But for this domain, I don’t see any request from the let’s encrypt server. The DNS looks fine, I can’t see any problem on our site. How do I debug, which request the let’s encrypt servers do exactly?