Interestingly, cloud-init-output.log, attached in comment # 3, is reporting these failures:
Something wicked happened resolving '10.5.0.10:3142' (-9 - Address family for hostname not supported) Err:12 http://security.ubuntu.com/ubuntu xenial-security/main amd64 libnspr4 amd64 2:4.12-0ubuntu0.16.04.1
Interestingly, cloud-init- output. log, attached in comment # 3, is reporting these failures:
Something wicked happened resolving '10.5.0.10:3142' (-9 - Address family for hostname not supported) security. ubuntu. com/ubuntu xenial- security/ main amd64 libnspr4 amd64 2:4.12- 0ubuntu0. 16.04.1
Err:12 http://