A connection between the subnets behind the gateways <b>moon</b> and <b>sun</b> is set up. The authentication is based on <b>X.509 certificates</b>. Upon the successful establishment of the IPsec tunnel, <b>leftfirewall=yes</b> automatically inserts iptables-based firewall rules that let pass the tunneled traffic. After a while the CHILD_SA is rekeyed by <b>moon</b> (after a deliberately short time in this test scenario). In order to test both tunnel and firewall after the rekeying, client <b>alice</b> behind gateway <b>moon</b> pings client <b>bob</b> located behind gateway <b>sun</b> twice, once right after the rekeying and once after the old inbound SA has been deleted.