公司的产品一直运行在云服务器上，从而有幸接触过aws的ec2，盛大的云服务器，最近准备有使用阿里云的弹性计算（云服务器）。前两种云服务器在安全策略这块做的比较好，提供简单明了的配置界面，而且给了默认的安全策略，反观阿里云服务器，安全策略需要自己去配置，甚至centos机器上都没有预装iptables（起码我们申请两台上都没有），算好可以使用yum来安装，安装命令如下：
yum install -y iptables
iptables安装好后就可以来配置规则了。由于作为web服务器来使用，所以对外要开放 80 端口，另外肯定要通过ssh进行服务器管理，22 端口也要对外开放，当然最好是把ssh服务的默认端口改掉，在公网上会有很多人试图破解密码的，如果修改端口，记得要把该端口对外开发，否则连不上就悲剧了。下面提供配置规则的详细说明：
第一步：清空所有规则当Chain INPUT (policy DROP)时执行/sbin/iptables -F后，你将和服务器断开连接所有在清空所有规则前把policy DROP该为INPUT，防止悲剧发生，小心小心再小心/sbin/iptables -P INPUT ACCEPT清空所有规则/sbin/iptables -F/sbin/iptables -X计数器置0/sbin/iptables -Z第二步：设置规则允许来自于lo接口的数据包，如果没有此规则，你将不能通过127.0.0.1访问本地服务，例如ping 127.0.0.1/sbin/iptables -A INPUT -i lo -j ACCEPT 开放TCP协议22端口，以便能ssh，如果你是在有固定ip的场所，可以使用 -s 来限定客户端的ip/sbin/iptables -A INPUT -p tcp --dport 22 -j ACCEPT开放TCP协议80端口供web服务/sbin/iptables -A INPUT -p tcp --dport 80 -j ACCEPT10.241.121.15是另外一台服务器的内网ip，由于之间有通信，接受所有来自10.241.121.15的TCP请求/sbin/iptables -A INPUT -p tcp -s 10.241.121.15 -j ACCEPT接受ping/sbin/iptables -A INPUT -p icmp -m icmp --icmp-type 8 -j ACCEPT这条规则参看：http://www.netingcn.com/iptables-localhost-not-access-internet.html/sbin/iptables -A INPUT -m state --state ESTABLISHED -j ACCEPT屏蔽上述规则以为的所有请求，不可缺少，否则防火墙没有任何过滤的功能/sbin/iptables -P INPUT DROP可以使用 iptables -L -n 查看规则是否生效
至此防火墙就算配置好，但是这是临时的，当重启iptables或重启机器，上述配置就会被清空，要想永久生效，还需要如下操作：
/etc/init.d/iptables save 或service iptables save执行上述命令可以在文件 /etc/sysconfig/iptables 中看到配置
以下提供一个干净的配置脚本：
/sbin/iptables -P INPUT ACCEPT/sbin/iptables -F/sbin/iptables -X/sbin/iptables -Z/sbin/iptables -A INPUT -i lo -j ACCEPT /sbin/iptables -A INPUT -p tcp --dport 22 -j ACCEPT/sbin/iptables -A INPUT -p tcp --dport 80 -j ACCEPT/sbin/iptables -A INPUT -p tcp -s 10.241.121.15 -j ACCEPT/sbin/iptables -A INPUT -p icmp -m icmp --icmp-type 8 -j ACCEPT/sbin/iptables -A INPUT -m state --state ESTABLISHED -j ACCEPT/sbin/iptables -P INPUT DROP
最后执行 service iptables save ，先确保ssh连接没有问题，防止规则错误，导致无法连上服务器，因为没有save，重启服务器规则都失效，否则就只有去机房才能修改规则了。也可以参考：ubuntu iptables 配置脚本来写一个脚本。
最后再次提醒，在清空规则之前一定要小心，确保Chain INPUT (policy ACCEPT)。
VEVB武林网补充阿里云的linux_drop_port.sh
#!/bin/bash##########################################Function: linux drop port#Usage: bash linux_drop_port.sh#Author: Customer Service Department#Company: Alibaba Cloud Computing#Version: 2.0######################################### check_os_release(){ while true do os_release=$(grep "Red Hat Enterprise Linux Server release"/etc/issue 2>/dev/null) os_release_2=$(grep "Red Hat Enterprise Linux Server release"/etc/redhat-release 2>/dev/null) if [ "$os_release" ] && [ "$os_release_2" ] then if echo "$os_release"|grep "release 5" >/dev/null2>&1 then os_release=redhat5 echo "$os_release" elif echo "$os_release"|grep "release 6">/dev/null 2>&1 then os_release=redhat6 echo "$os_release" else os_release="" echo "$os_release" fi break fi os_release=$(grep "Aliyun Linux release" /etc/issue2>/dev/null) os_release_2=$(grep "Aliyun Linux release" /etc/aliyun-release2>/dev/null) if [ "$os_release" ] && [ "$os_release_2" ] then if echo "$os_release"|grep "release 5" >/dev/null2>&1 then os_release=aliyun5 echo "$os_release" elif echo "$os_release"|grep "release 6">/dev/null 2>&1 then os_release=aliyun6 echo "$os_release" else os_release="" echo "$os_release" fi break fi os_release=$(grep "CentOS release" /etc/issue 2>/dev/null) os_release_2=$(grep "CentOS release" /etc/*release2>/dev/null) if [ "$os_release" ] && [ "$os_release_2" ] then if echo "$os_release"|grep "release 5" >/dev/null2>&1 then os_release=centos5 echo "$os_release" elif echo "$os_release"|grep "release 6">/dev/null 2>&1 then os_release=centos6 echo "$os_release" else os_release="" echo "$os_release" fi break fi os_release=$(grep -i "ubuntu" /etc/issue 2>/dev/null) os_release_2=$(grep -i "ubuntu" /etc/lsb-release2>/dev/null) if [ "$os_release" ] && [ "$os_release_2" ] then if echo "$os_release"|grep "Ubuntu 10" >/dev/null2>&1 then os_release=ubuntu10 echo "$os_release" elif echo "$os_release"|grep "Ubuntu 12.04">/dev/null 2>&1 then os_release=ubuntu1204 echo "$os_release" elif echo "$os_release"|grep "Ubuntu 12.10">/dev/null 2>&1 then os_release=ubuntu1210 echo "$os_release" else os_release="" echo "$os_release" fi break fi os_release=$(grep -i "debian" /etc/issue 2>/dev/null) os_release_2=$(grep -i "debian" /proc/version 2>/dev/null) if [ "$os_release" ] && [ "$os_release_2" ] then if echo "$os_release"|grep "Linux 6" >/dev/null2>&1 then os_release=debian6 echo "$os_release" else os_release="" echo "$os_release" fi break fi os_release=$(grep "openSUSE" /etc/issue 2>/dev/null) os_release_2=$(grep "openSUSE" /etc/*release 2>/dev/null) if [ "$os_release" ] && [ "$os_release_2" ] then if echo "$os_release"|grep"13.1" >/dev/null 2>&1 then os_release=opensuse131 echo "$os_release" else os_release="" echo "$os_release" fi break fi break done} exit_script(){ echo -e "/033[1;40;31mInstall $1 error,will exit./n/033[0m" rm-f $LOCKfile exit 1} config_iptables(){ iptables -I OUTPUT 1 -p tcp -m multiport --dport21,22,23,25,53,80,135,139,443,445 -j DROP iptables -I OUTPUT 2 -p tcp -m multiport --dport 1433,1314,1521,2222,3306,3433,3389,4899,8080,18186-j DROP iptables -I OUTPUT 3 -p udp -j DROP iptables -nvL} ubuntu_config_ufw(){ ufwdeny out proto tcp to any port 21,22,23,25,53,80,135,139,443,445 ufwdeny out proto tcp to any port 1433,1314,1521,2222,3306,3433,3389,4899,8080,18186 ufwdeny out proto udp to any ufwstatus} ####################Start####################check lock file ,one time only let thescript run one timeLOCKfile=/tmp/.$(basename $0)if [ -f "$LOCKfile" ]then echo -e "/033[1;40;31mThe script is already exist,please next timeto run this script./n/033[0m" exitelse echo -e "/033[40;32mStep 1.No lock file,begin to create lock fileand continue./n/033[40;37m" touch $LOCKfilefi #check userif [ $(id -u) != "0" ]then echo -e "/033[1;40;31mError: You must be root to run this script,please use root to execute this script./n/033[0m" rm-f $LOCKfile exit 1fi echo -e "/033[40;32mStep 2.Begen tocheck the OS issue./n/033[40;37m"os_release=$(check_os_release)if [ "X$os_release" =="X" ]then echo -e "/033[1;40;31mThe OS does not identify,So this script isnot executede./n/033[0m" rm-f $LOCKfile exit 0else echo -e "/033[40;32mThis OS is $os_release./n/033[40;37m"fi echo -e "/033[40;32mStep 3.Begen toconfig firewall./n/033[40;37m"case "$os_release" inredhat5|centos5|redhat6|centos6|aliyun5|aliyun6) service iptables start config_iptables ;;debian6) config_iptables ;;ubuntu10|ubuntu1204|ubuntu1210) ufwenable <<EOFyEOF ubuntu_config_ufw ;;opensuse131) config_iptables ;;esac echo -e "/033[40;32mConfig firewallsuccess,this script now exit!/n/033[40;37m"rm -f $LOCKfile上述文件下载到机器内部直接执行即可。
新闻热点
疑难解答
