OpenSSL::SSL::SSLError: hostname does not match the server certificate

Question

All of sudden today morning my HTTP client (HTTParty) threw an error OpenSSL::SSL::SSLError: hostname does not match the server certificate

Firs

Answer 1

It's hard to be sure without knowing host you are connecting too, but I guess that they simply changed the certificate at the servers end. The problem might be, that your script does not support SNI (server name indication, e.g. multiple host names and certificates behind the same IP), but the server providers now changed the default certificate for this site (the one which is used if client does not support SNI).

But like I said, it's hard to be sure with this lack of details in the question.