iptables -t nat -F
nic #
 iptables -F
nic #
 iptables -X
nic #
 # NAT
nic #
 ip addr show dev eth1 | grep 192.1.33.254 || ip addr add 192.1.33.254/24 dev eth1
nic #
 iptables -t nat -A POSTROUTING -p udp --sport 4500 -j SNAT --to-source 192.1.2.254:3500-3700
nic #
 iptables -t nat -A POSTROUTING -p udp --sport 500 -j SNAT --to-source 192.1.2.254:2500-2700
nic #
 iptables -t nat -A POSTROUTING --destination 0.0.0.0/0 -j SNAT --to-source 192.1.2.254
nic #
 iptables -t nat -L -n
Chain PREROUTING (policy ACCEPT)
target     prot opt source               destination         
Chain INPUT (policy ACCEPT)
target     prot opt source               destination         
Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination         
Chain POSTROUTING (policy ACCEPT)
target     prot opt source               destination         
SNAT       udp  --  0.0.0.0/0            0.0.0.0/0            udp spt:4500 to:192.1.2.254:3500-3700
SNAT       udp  --  0.0.0.0/0            0.0.0.0/0            udp spt:500 to:192.1.2.254:2500-2700
SNAT       all  --  0.0.0.0/0            0.0.0.0/0            to:192.1.2.254
nic #
 iptables -L -n
Chain INPUT (policy ACCEPT)
target     prot opt source               destination         
Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         
Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination         
nic #
 echo initdone
initdone

