Nothing particular.
As container name, set “name.domain.tld”

Source: https://docs.nethserver.org/en/v7/installation.html

# yum install -y http://mirror.nethserver.org/nethserver/nethserver-release-7.rpm
# nethserver-install 

After the installation of NethServer, the network configuration of the CT is “gone” and need to be reconfigured. Test a ping!
From the console of the CT NethServer (adapt the IP and the network to yours!):

# db networks set eth0 ethernet role green ipaddr 192.168.20.225 netmask 255.255.255.0 network 192.168.20.0 onboot yes bootproto static
# signal-event interface-update 

Source: https://community.nethserver.org/t/chronyd-does-not-start/9946/3

My guess is that chrony does not work in a lxc container because date and time are handled by the hypervisor.

⇒ service stays disabled.