The roadwarriors carol and dave set up a connection each to gateway moon.
Both carol and dave request a virtual IP via the IKEv2 configuration payload
by using the leftsourceip=%config parameter. leftfirewall=yes automatically
inserts iptables-based firewall rules that let pass the tunneled traffic. In order to test the
tunnels, carol and dave then ping the client alice behind the gateway
moon. The source IP addresses of the two pings will be the virtual IPs carol1
and dave1, respectively.