Open port vs open | filtered port
by maddy0 from LinuxQuestions.org on (#6NAGQ)
Hi, I can't find anything on this specific topic....to "surf the web", you have to open certain ports, 53 (DNS), for example. The question I would like to ask is:
what is the difference between open port and open | filtered port.
iptables -A INPUT -p udp -i enp5s0 --sport 53 -j ACCEPT
iptables -A OUTPUT -p udp -o enp5s0 --dport 53 -j ACCEPT
These two rules open port 53 in and out to my connection, but the port, I think, turns out to be open and not open|filtered.
I am attaching a screenshot from a user (who did not receive an answer), but who was asking the same question. I hope I have been clear.
Attached Thumbnails
what is the difference between open port and open | filtered port.
iptables -A INPUT -p udp -i enp5s0 --sport 53 -j ACCEPT
iptables -A OUTPUT -p udp -o enp5s0 --dport 53 -j ACCEPT
These two rules open port 53 in and out to my connection, but the port, I think, turns out to be open and not open|filtered.
I am attaching a screenshot from a user (who did not receive an answer), but who was asking the same question. I hope I have been clear.
Attached Thumbnails