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  •  agriz
      agriz
iptables blocks dns
#35
Regular Board Member
Joined: 2011/11/19
From
Posts: 81
When i stop iptables

nslookup site.com


Server: dns ip
Address: dns ip#53

Non-authoritative answer:
Name: site.com
Address: ipaddress

When i start iptables,

;; connection timed out; no servers could be reached

Why does iptables blocks dns?


iptables -P INPUT DROP
iptables -P FORWARD DROP
iptables -P OUTPUT ACCEPT


iptables -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT

iptables -I INPUT 1 -i lo -j ACCEPT
iptables -I OUTPUT 1 -o lo -j ACCEPT

//ssh
iptables -A INPUT -i eth0 -p tcp --dport 1234 -m state --state NEW,ESTABLISHED -j ACCEPT
iptables -A OUTPUT -o eth0 -p tcp --sport 1234 -m state --state ESTABLISHED -j ACCEPT

iptables -A INPUT -i eth0 -p icmp --icmp-type echo-request -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT
iptables -A OUTPUT -o eth0 -p icmp --icmp-type echo-reply -m state --state ESTABLISHED,RELATED -j ACCEPT

iptables -A INPUT -i eth0 -p icmp --icmp-type echo-reply -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT
iptables -A OUTPUT -o eth0 -p icmp --icmp-type echo-request -m state --state ESTABLISHED,RELATED -j ACCEPT


iptables -A INPUT -i eth0 -p tcp --dport 80 -m state --state NEW,ESTABLISHED -j ACCEPT
iptables -A OUTPUT -o eth0 -p tcp --sport 80 -m state --state ESTABLISHED -j ACCEPT

iptables -A INPUT -i eth0 -p tcp --dport 443 -m state --state NEW,ESTABLISHED -j ACCEPT
iptables -A OUTPUT -o eth0 -p tcp --sport 443 -m state --state ESTABLISHED -j ACCEPT


iptables -A OUTPUT -p udp -o eth0 --dport 53 --sport 1024:65535 -j ACCEPT
iptables -A INPUT -p udp -i eth0 --sport 53 --dport 1024:65535 -j ACCEPT

iptables -A INPUT -m state --state NEW -m tcp -p tcp --dport 25 -j ACCEPT


This is what i entered in iptables.
Posted on: 2011/12/8 19:04
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Subject Poster Date
     Re: iptables blocks dns TrevorH 2011/12/8 20:31
       Re: iptables blocks dns agriz 2011/12/8 20:49
         Re: iptables blocks dns TrevorH 2011/12/8 21:01
           Re: iptables blocks dns agriz 2011/12/8 21:10
             Re: iptables blocks dns TrevorH 2011/12/8 21:20
               Re: iptables blocks dns agriz 2011/12/8 21:28
                 Re: iptables blocks dns agriz 2011/12/8 21:30
                   Re: iptables blocks dns TrevorH 2011/12/8 21:46
                     Re: iptables blocks dns agriz 2011/12/8 21:52
                       Re: iptables blocks dns TrevorH 2011/12/8 22:18
                         Re: iptables blocks dns agriz 2011/12/8 22:32
                           Re: iptables blocks dns TrevorH 2011/12/8 22:43
                             Re: iptables blocks dns agriz 2011/12/8 22:53
                               Re: iptables blocks dns TrevorH 2011/12/8 23:17
                                 Re: iptables blocks dns agriz 2011/12/8 23:30
                                   Re: iptables blocks dns TrevorH 2011/12/8 23:40
                                     Re: iptables blocks dns agriz 2011/12/8 23:46
                                       Re: iptables blocks dns TrevorH 2011/12/8 23:52
                                         Re: iptables blocks dns agriz 2011/12/8 23:54
                                           Re: iptables blocks dns agriz 2011/12/9 19:08
                                             Re: iptables blocks dns TrevorH 2011/12/9 19:46
                                               Re: iptables blocks dns agriz 2011/12/9 21:15
                                                 Re: iptables blocks dns TrevorH 2011/12/9 21:42
                                                   Re: iptables blocks dns agriz 2011/12/9 21:51
                                                     Re: iptables blocks dns agriz 2011/12/9 22:04
                                                       Re: iptables blocks dns TrevorH 2011/12/9 23:14
                                                         Re: iptables blocks dns agriz 2011/12/9 23:18
                                                           Re: iptables blocks dns TrevorH 2011/12/9 23:29
                                                             Re: iptables blocks dns agriz 2011/12/9 23:30
                                                               Re: iptables blocks dns TrevorH 2011/12/9 23:32
                                                                 Re: iptables blocks dns agriz 2011/12/9 23:36
                                                                   Re: iptables blocks dns agriz 2011/12/9 23:52
                                                                     Re: iptables blocks dns agriz 2011/12/10 0:07
                                                           Re: iptables blocks dns agriz 2011/12/9 23:27
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