iptables state 状态防火墙_Linux教程_Linux公社-Linux系统门户网站
$ cat /etc/sysconfig/iptables *filter :INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [214:43782] -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT -A Netfilter is a framework provided by the Linux kernel that allows various networking-related operations to be implemented in the form of customized handlers.Netfilter offers various functions and operations for packet filtering, network address translation, and port translation, which provide the functionality required for directing packets through a network and prohibiting packets from # Generated by iptables-save v1.4.12 on Wed Dec 7 20:22:39 2011 *filter :INPUT DROP [157:36334] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [48876:76493439] -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT -A INPUT -p icmp -j ACCEPT -A INPUT -i lo -j ACCEPT -A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT COMMIT # Completed on 環境 CentOS release 6.4 (Final) iptables.i686 1.4.7-9.el6 方針 以下の大原則に従う設定を作ることとする。 自ホストからの通信は通してやる。 外からのpingは通
iptables -A INPUT -p tcp --dport 22 -m state NEW --state -m recent --set iptables -A INPUT -p tcp --dport 22 -m state --state NEW -m recent --update --seconds 100 --hitcount 10 -j DROP When I search online I always see NEW being used in that rule but I'm having a hard time understanding why ESTABLISHED and RELATED aren't being used.
All computers in my VLAN can ping 8.8.8.8 + google.fr, use ntp, dns dhcp but they are not able to browse any internet page on mozilla or ice. When I put iptables input, forward, output on ACCEPT and flush previous rules the computers can browse internet again. I'm getting with hairs withe, don't know whats wrong.
Oct 22, 2011 · iptables -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT iptables -A INPUT -i lo -j ACCEPT iptables -A INPUT -m state --state NEW -p tcp --dport 80 -j ACCEPT
iptables -A INPUT -p tcp --dport 22 -m state NEW --state -m recent --set iptables -A INPUT -p tcp --dport 22 -m state --state NEW -m recent --update --seconds 100 --hitcount 10 -j DROP When I search online I always see NEW being used in that rule but I'm having a hard time understanding why ESTABLISHED and RELATED aren't being used. iptables(8)-A INPUT-m state--state ESTABLISHED,RELATED-j ACCEPT administration tool for IPv4 packet filtering and NAT -A , --append chain rule-specification Append one or more rules to the end of the selected chain. Dec 09, 2019 · iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT This is the rule that does most of the work, and again we are adding (-A) it to the INPUT chain. Here we're using the -m switch to load a module (state). The state module is able to examine the state of a packet and determine if it is NEW, ESTABLISHED or RELATED. Apr 11, 2020 · sudo iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT. Allowing Incoming Traffic on Specific Ports. You could start by blocking traffic, but you might be working over SSH, where you would need to allow SSH before blocking everything else. Aug 29, 2017 · iptables-A INPUT -p tcp -m multiport ! --dports 22,80,443 -j DROP. However, you should first accept packets from established and related connections before using this rule! If you don’t, you’ll find out that you can’t use any TCP based applications. This is because legitimate TCP traffic would be dropped, too.