root@deor:/etc/firehol# firehol stop
root@deor:/etc/firehol# iptables -t nat -A POSTROUTING -j SNAT --to-source 11.22.33.44
root@deor:/etc/firehol# iptables -L
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
root@deor:/etc/firehol# iptables -t nat -n -L
Chain PREROUTING (policy ACCEPT)
target     prot opt source               destination

Chain POSTROUTING (policy ACCEPT)
target     prot opt source               destination
SNAT       all  --  0.0.0.0/0            0.0.0.0/0           to:11.22.33.44

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination