16.04的/etc/network/interfaces已经没用了，用新工具netplan

Multiple addresses on an interface
The addresses key can take a list of addresses to assign to an interface:

network:
  version: 2
  renderer: networkd
  ethernets:
    enp3s0:
     addresses:
       - 10.100.1.38/24
       - 10.100.1.39/24
     gateway4: 10.100.1.1

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