Ubuntu 18.04 server configured with static ipv6 request dhcp ipv6 address

I'm having trouble understanding why an Ubuntu 18.04 LTS server installed on a bhyve host insists on requesting a dhcpv6 address despite being configured with a static address with dhcp6 off.

root@ubs:~# journalctl -u systemd-networkd ... -- Reboot --
Feb 15 14:01:45 ubs systemd[1]: Starting Network Service...
Feb 15 14:01:45 ubs systemd-networkd[584]: Enumeration completed
Feb 15 14:01:45 ubs systemd[1]: Started Network Service.
Feb 15 14:01:45 ubs systemd-networkd[584]: lo: Link is not managed by us
Feb 15 14:01:45 ubs systemd-networkd[584]: enp0s4: IPv6 successfully enabled
Feb 15 14:01:45 ubs systemd-networkd[584]: enp0s4: Gained carrier
Feb 15 14:01:46 ubs systemd-networkd[584]: enp0s4: Gained IPv6LL
Feb 15 14:01:48 ubs systemd-networkd[584]: enp0s4: DHCPv6 address 2a02:2f04:...::941a/128 timeout preferred 4500 valid 7200
Feb 15 14:01:50 ubs systemd-networkd[584]: enp0s4: Configured root@ubs:~# networkctl status enp0s4 ● 2: enp0s4 Link File: /lib/systemd/network/99-default.link Network File: /run/systemd/network/10-netplan-enp0s4.network Type: ether State: routable (configured) Path: pci-0000:00:04.0 Driver: virtio_net Vendor: Red Hat, Inc. Model: Virtio network device HW Address: 00:a0:98:7a:8e:aa (NetApp) Address: 10.0.200.11 2a02:2f04:...::51 2a02:2f04:...::941a 2a02:2f04:146:...:8eaa fe80::2a0:98ff:fe7a:8eaa Gateway: 10.0.200.1 DNS: 2a02:2f04:...::1 Search Domains: domain.tld root@ubs:~#

But DHCP v6 is NOT configured:

root@ubs:~# cat /etc/netplan/50-cloud-init.yaml
# This file is generated from information provided by
# the datasource. Changes to it will not persist across an instance.
# To disable cloud-init's network configuration capabilities, write a file
# /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg with the following:
# network: {config: disabled}
network: ethernets: enp0s4: addresses: - 10.0.200.11/24 - 2a02:2f04:...::51/64 dhcp4: false dhcp6: false gateway4: 10.0.200.1 gateway6: 2a02:2f04:...::1 nameservers: addresses: - 2a02:2f04:...::1 search: - domain.tld version: 2
root@ubs:~#

Who's sending the solicit message? is this a bug or i'm overlooking something obvious?

1 Answer

false is not an option according to the examples on the netplan website. However, the netplan reference page states (bool), which makes true/false first guess.

dhcp4: yes/no
dhcp6: yes/no