How to verify iptables tool
On D02
iptables -A INPUT -s <172.18.45.13> -j REJECT -> set the rule to reject the packets
iptables -L -> shows the added rule
Where
172.18.45.60 - ip address of D02 board and
172.18.45.13 - ip address of the PC.
On PC
ping <172.18.45.60> -> unreachable as packets are rejected based on above iptables rule.
On D02
iptables -D INPUT 1 -> delete the rule.
iptables -A INPUT -s <172.18.45.13> -j ACCEPT -> set the rule to accept the packets
iptables -L -> shows the added rule
ON PC
ping <172.18.45.60> -> work ok as packets are accpeted.