Chain INPUT (policy ACCEPT 1812 packets, 194K bytes)
 pkts bytes target     prot opt in     out     source               destination                                              

Chain FORWARD (policy ACCEPT 185K packets, 161M bytes)
 pkts bytes target     prot opt in     out     source               destination                                              
    0     0 ACCEPT     esp  --  *      *       0.0.0.0/0            10.40.56.19                                              
    0     0 ACCEPT     udp  --  *      *       0.0.0.0/0            10.40.56.19                                                      udp dpt:500

Chain OUTPUT (policy ACCEPT 1396 packets, 165K bytes)
 pkts bytes target     prot opt in     out     source               destination                                              
Chain PREROUTING (policy ACCEPT 1883 packets, 119K bytes)
 pkts bytes target     prot opt in     out     source               destination                                              
    0     0 DNAT       esp  --  *      *       0.0.0.0/0            0.0.0.0/0                                                        to:10.40.56.19
    0     0 DNAT       udp  --  *      *       0.0.0.0/0            10.40.56.19                                                      udp dpt:500 to:10.40.56.19:500

Chain POSTROUTING (policy ACCEPT 109 packets, 10211 bytes)
 pkts bytes target     prot opt in     out     source               destination                                              
   25  1224 MASQUERADE  all  --  *      eth0    10.40.56.168         0.0.0.0/0                                               
   66  3168 MASQUERADE  all  --  *      eth0    10.40.56.170         0.0.0.0/0                                               
    0     0 MASQUERADE  all  --  *      eth0    10.40.56.175         0.0.0.0/0                                               
    0     0 MASQUERADE  all  --  *      eth0    10.40.56.178         0.0.0.0/0                                               
   47  2256 MASQUERADE  all  --  *      eth0    10.40.56.176         0.0.0.0/0                                               
    0     0 MASQUERADE  all  --  *      eth0    10.40.56.177         0.0.0.0/0                                               
    0     0 MASQUERADE  all  --  *      eth0    10.40.56.179         0.0.0.0/0                                               
    0     0 MASQUERADE  all  --  *      eth0    10.40.56.182         0.0.0.0/0                                               
    0     0 MASQUERADE  all  --  *      eth0    10.40.56.183         0.0.0.0/0                                               
    0     0 MASQUERADE  all  --  *      eth0    10.40.56.193         0.0.0.0/0                                               
    0     0 MASQUERADE  all  --  *      eth0    10.40.56.195         0.0.0.0/0                                               
  388 18624 MASQUERADE  all  --  *      eth0    10.40.56.81          0.0.0.0/0                                               
    0     0 MASQUERADE  all  --  *      eth0    10.40.56.191         0.0.0.0/0                                               
    0     0 MASQUERADE  all  --  *      eth0    10.40.56.181         0.0.0.0/0                                               
    0     0 MASQUERADE  all  --  *      eth0    10.40.56.18          0.0.0.0/0                                               
    0     0 MASQUERADE  all  --  *      eth0    10.40.56.19          0.0.0.0/0                                               

Chain OUTPUT (policy ACCEPT 8 packets, 515 bytes)
 pkts bytes target     prot opt in     out     source               destination