Hello,

Im new on centos server and im trying to disable firewalld and work with iptables

So i read about it and did the following :

Disable firewalld , this is my systemctl status firewalld

● firewalld.service
Loaded: masked (/dev/null; bad)
Active: inactive (dead)

And this is my iptables -L

Chain INPUT (policy ACCEPT)
target prot opt source destination
ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED
ACCEPT icmp -- anywhere anywhere
ACCEPT all -- anywhere anywhere
ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:ssh
REJECT all -- anywhere anywhere reject-with icmp-host-prohibited
DROP tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,PSH,ACK,URG/FIN,SYN,RST,PSH,ACK,URG
ACCEPT tcp -- anywhere anywhere tcp dpt:domain state NEW,ESTABLISHED
ACCEPT udp -- anywhere anywhere udp dpt:domain state NEW,ESTABLISHED
ACCEPT tcp -- anywhere anywhere tcp spt:domain state NEW,ESTABLISHED
ACCEPT udp -- anywhere anywhere udp spt:domain state NEW,ESTABLISHED

Chain FORWARD (policy ACCEPT)
target prot opt source destination
REJECT all -- anywhere anywhere reject-with icmp-host-prohibited

Chain OUTPUT (policy ACCEPT)
target prot opt source destination
ACCEPT tcp -- anywhere anywhere tcp dpt:domain state ESTABLISHED
ACCEPT udp -- anywhere anywhere udp dpt:domain state ESTABLISHED
ACCEPT udp -- anywhere anywhere udp spt:domain state ESTABLISHED
ACCEPT tcp -- anywhere anywhere tcp spt:domain state ESTABLISHED


Why is my DNS not working ? I do not understand .

In your INPUT chain you have:
REJECT all -- anywhere anywhere reject-with icmp-host-prohibited

You then have your other statements below that but that one is saying reject everything so nothing gets to the other rules in that chain. You need to make the above rule the LAST one in your INPUT chain.

You also want to verify domain = port 53 in /etc/services. (It normally is but checking doesn't hurt.)

You really ought to learn to do firewalld - it isn't that difficult. I use it on my DNS server running RHEL7.

1 members found this post helpful.

Tanks man!!!

I did not see this rule, or rather, I saw but did not notice that it effected the other.

I have done some rules with firewalld but i'm studying to do the LFCE exam so im testing a lot of thing