I am also facing this issue. Your settings seems to fix it thank you. Just and a note the issue also exist in debain 9
-- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to isc-dhcp in Ubuntu. https://bugs.launchpad.net/bugs/1604617 Title: dhclient does not send fqdn.fqdn for DHCPv6 Status in isc-dhcp package in Ubuntu: Confirmed Bug description: ISC DHCP's dynamic DNS updates rely on the fqdn.fqdn option being sent in order to work for DHCPv6. This used to be done in Ubuntu, as shown in bugs #991360 and #108862, and all my Windows hosts send it. However this was removed in Ubuntu due to a regression in IPv4 functionality. As IPv6 is more widely deployed these days, this regression in IPv6 should be fixed. This bug is current as of Ubuntu 16.04 LTS. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/isc-dhcp/+bug/1604617/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
