Wrong IP address from DHCP client on Ubuntu 18.04dhcp ubuntu ip
The cause of the problem is that the built-in network config of Ubuntu 18.04 no longer uses the NIC Mac address as the default id for DHCP requests.
It can be restored by adding
dhcp-identifier: mac to the configuration in the
/etc/netplan/xxx.yaml (cloud-init) file as follows:
network: version: 2 ethernets: ens3: dhcp4: true dhcp-identifier: mac