The roadwarriors <b>carol</b> and <b>dave</b> set up a connection each to gateway <b>moon</b> using the <b>MODP Diffie-Hellman Groups 22, 23, and 24</b> with <b>Prime Order Subgroups</b>. <p/> <b>carol</b> proposes the DH groups MODP_2048_224 and MODP_1024_160 whereas <b>dave</b> proposes MODP_2048_224 and MODP_2048_256. Since <b>moon</b> does not support MODP_2048_224 the roadwarriors fall back to MODP_1024_160 and MODP_2048_256, respectively. <p/> Upon the successful establishment of the IPsec tunnels, <b>leftfirewall=yes</b> automatically inserts iptables-based firewall rules that let pass the tunneled traffic. In order to test both tunnel and firewall, both <b>carol</b> and <b>dave</b> ping the client <b>alice</b> behind the gateway <b>moon</b>.