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. The gateway moon assigns virtual IP addresses from a simple pool defined by rightsourceip=10.3.0.0/28 in a monotonously increasing order.

Using the ipsec lookup tool which communicates with the lookip plugin via a unix socket, information about the assigned virtual IP is retrieved.

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.