The roadwarriors <b>carol</b> and <b>dave</b> set up a connection each to gateway <b>moon</b>.
Both <b>carol</b> and <b>dave</b> request a <b>virtual IP</b> via the IKEv1 Mode Config
payload by using the <b>vips = 0.0.0.0</b> parameter.
<b>moon</b> assigns virtual IP addresses from a simple pool defined in the pools section
of swanctl.conf in a monotonously increasing order.
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Upon the successful establishment of the IPsec tunnel, the updown script automatically
inserts iptables-based firewall rules that let pass the tunneled traffic. In order to
test the tunnels, <b>carol</b> and <b>dave</b> then ping the client <b>alice</b> behind
the gateway <b>moon</b>. The source IP addresses of the two pings will be the virtual
IPs <b>10.3.0.1</b> and <b>10.3.0.2</b>, respectively.
