Let's Debug

Test result for snf-45288.vm.okeanos-global.grnet.gr using http-01

A fatal issue occurred during the DNS lookup process for grnet.gr/CAA.
DNS response for grnet.gr/CAA did not have an acceptable response code: SERVFAIL
A fatal issue occurred during the DNS lookup process for snf-45288.vm.okeanos-global.grnet.gr/A.
DNS response for snf-45288.vm.okeanos-global.grnet.gr/A did not have an acceptable response code: SERVFAIL
A fatal issue occurred during the DNS lookup process for snf-45288.vm.okeanos-global.grnet.gr/AAAA.
DNS response for snf-45288.vm.okeanos-global.grnet.gr/AAAA did not have an acceptable response code: SERVFAIL
Fatal
No valid A or AAAA records could be ultimately resolved for snf-45288.vm.okeanos-global.grnet.gr. This means that Let's Encrypt would not be able to to connect to your domain to perform HTTP validation, since it would not know where to connect to.
No A or AAAA records found.

Submitted Jan 15 06:22:02 2019. Sat in queue for 3ms. Completed in 16s. Show verbose information.