On Router 4, issue a ping command to the so-0/0/0 interface on Router 1 to send traffic across the IPSec tunnel.
user@R4> ping 10.1.12.2
PING 10.1.12.2 (10.1.12.2): 56 data bytes 64 bytes from 10.1.12.2: icmp_seq=0 ttl=254 time=1.350 ms 64 bytes from 10.1.12.2: icmp_seq=1 ttl=254 time=1.161 ms 64 bytes from 10.1.12.2: icmp_seq=2 ttl=254 time=1.124 ms 64 bytes from 10.1.12.2: icmp_seq=3 ttl=254 time=1.142 ms 64 bytes from 10.1.12.2: icmp_seq=4 ttl=254 time=1.139 ms 64 bytes from 10.1.12.2: icmp_seq=5 ttl=254 time=1.116 ms ^C --- 10.1.12.2 ping statistics --- 6 packets transmitted, 6 packets received, 0% packet loss round-trip min/avg/max/stddev = 1.116/1.172/1.350/0.081 ms
Again, the traceroute command verifies that traffic to 10.1.12.2 travels over the IPSec tunnel between Router 3 and Router 2. Notice that the second hop does not reference 10.1.15.1—the physical interface on Router 2. Instead, the second hop is listed as unknown with the *** notation. This indicates that the IPSec tunnel is operating correctly.
user@R4> traceroute 10.1.12.2
traceroute to 10.1.12.2 (10.1.12.2), 30 hops max, 40 byte packets 1 10.1.56.1 (10.1.56.1) 3.561 ms 0.613 ms 0.558 ms 2 * * * 3 10.1.12.2 (10.1.12.2) 1.073 ms 0.862 ms 0.818 ms