attend-class.com has both AAAA (IPv6) and A (IPv4) records. While they both appear to be accessible on the network, we have detected that they produce differing results when sent an ACME HTTP validation request. This may indicate that the IPv4 and IPv6 addresses may unintentionally point to different servers, which would cause validation to fail.
[Address Type=IPv4,Server=nginx/1.10.3 (Ubuntu),HTTP Status=301,Number of Redirects=1,Final HTTP Status=404] vs [Address Type=IPv6,Server=nginx/1.10.3 (Ubuntu),HTTP Status=404]
Requests made to the domain
Request to: attend-class.com/2600:3c00::f03c:91ff:fe07:bcbc, Result: [Address Type=IPv6,Server=nginx/1.10.3 (Ubuntu),HTTP Status=404], Issue:
Trace:
@0ms: Making a request to http://attend-class.com/.well-known/acme-challenge/letsdebug-test (using initial IP 2600:3c00::f03c:91ff:fe07:bcbc)
@0ms: Dialing 2600:3c00::f03c:91ff:fe07:bcbc
@76ms: Server response: HTTP 404 Not Found
Request to: attend-class.com/45.33.8.248, Result: [Address Type=IPv4,Server=nginx/1.10.3 (Ubuntu),HTTP Status=301,Number of Redirects=1,Final HTTP Status=404], Issue:
Trace:
@0ms: Making a request to http://attend-class.com/.well-known/acme-challenge/letsdebug-test (using initial IP 45.33.8.248)
@0ms: Dialing 45.33.8.248
@79ms: Server response: HTTP 301 Moved Permanently
@79ms: Received redirect to https://attend-class.com/.well-known/acme-challenge/letsdebug-test
@79ms: Dialing 45.33.8.248
@234ms: Server response: HTTP 404 Not Found
A and AAAA records found for this domain
attend-class.com. 0 IN A 45.33.8.248
attend-class.com. 0 IN AAAA 2600:3c00::f03c:91ff:fe07:bcbc
Challenge update failures for attend-class.com in order https://acme-staging-v02.api.letsencrypt.org/acme/order/5751349/7534745
acme: error code 403 "urn:ietf:params:acme:error:unauthorized": Invalid response from http://attend-class.com/.well-known/acme-challenge/rCslsav0klgzGDsHENLTsvhf80jyY6DDsiRl8TVR3pI: "<html>
<head><title>404 Not Found</title></head>
<body bgcolor="white">
<center><h1>404 Not Found</h1></center>
<hr><center>"
The IANA public suffix is the TLD of the Registered Domain
The TLD for attend-class.com is: com
The current status.io status for Let's Encrypt
Operational