LXD

$ lxc profile show dualnic
config: {}
description: Default LXD profile
devices:
  eth0:
    name: eth0
    nictype: bridged
    parent: br0
    type: nic
  eth1:
    name: eth1
    nictype: bridged
    parent: natbr0
    type: nic
  root:
    path: /
    pool: storage
    type: disk
name: dualnic
used_by: []
artur@nas:~$ lxc launch ubuntu:18.04 test -p dualnic
Creating test
Starting test
artur@nas:~$ lxc exec test bash
root@test:~# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
16: eth0@if17: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 00:16:3e:41:1e:b8 brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet 172.19.92.178/24 brd 172.19.92.255 scope global dynamic eth0
       valid_lft 86370sec preferred_lft 86370sec
    inet6 fe80::216:3eff:fe41:1eb8/64 scope link
       valid_lft forever preferred_lft forever
18: eth1@if19: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 00:16:3e:62:d8:cf brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet6 fe80::216:3eff:fe62:d8cf/64 scope link
       valid_lft forever preferred_lft forever
root@test:~# 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:
    version: 2
    ethernets:
        eth0:
            dhcp4: true