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Specify static IPs per container name (you can also use the container's mac address in situations of multiple network interfaces) (I have not tried or tested yet). To avoid conflicts, make sure the static IP addresses are outside of the range specified in /etc/default/lxc-net. (... investigate later, when using macvlan, can I specify the external IP address here too?)In case of multiple ip addresses look at LXC Advanced Networking.
Make sure to turn off your containers and then restart the Host OS. It seems though, that a certain amount of time is needed for whatever is touching lxc-net to register the changes. (find out how to flush this).
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