Default Chain Policy
As you notice below, it says “(policy ACCEPT)” next to all the three chain names (INPUT, OUTPUT, and FORWARD). This indicates that the default chain policy is ACCEPT.
# iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination
ACCEPT tcp — anywhere anywhere tcp dpt:ssh
DROP all — anywhere anywhere
Chain FORWARD (policy ACCEPT)
target prot opt source destination
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
So, you have two options here. (more…)