The server could not connect to the client to verify the domain

[schoen]

@Cqc

1. In the apache error log, Warning: DocumentRoot [/var/lib/letsencrypt/tls_sni_01_page/] does not exist

I don't think this error matters because there are no files being served in the TLS-SNI-01 challenge. I think this error is common and doesn't prevent validations from succeeding (though perhaps we should do something to eliminate it).