首先需要进行linux的基础安全设置,可以先参考这篇文章
https://www.jb51.net/article/94842.htm
1、Linux系统脚本
#!/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 $LOCKfile exit 1 } config_iptables() { iptables -I OUTPUT 1 -p tcp -m multiport --dport21,22,23,25,53,80,135,139,443,445 -j DROP iptables -I OUTPUT 2 -p tcp -m multiport --dport 1433,1314,1521,2222,3306,3433,3389,4899,8080,18186-j DROP iptables -I OUTPUT 3 -p udp -j DROP iptables -nvL } ubuntu_config_ufw() { ufwdeny out proto tcp to any port 21,22,23,25,53,80,135,139,443,445 ufwdeny out proto tcp to any port 1433,1314,1521,2222,3306,3433,3389,4899,8080,18186 ufwdeny out proto udp to any ufwstatus } ####################Start################### #check lock file ,one time only let thescript run one time LOCKfile=/tmp/.$(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" exit else echo -e "\033[40;32mStep 1.No lock file,begin to create lock fileand continue.\n\033[40;37m" touch $LOCKfile fi #check user if [ $(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 $LOCKfile exit 1 fi echo -e "\033[40;32mStep 2.Begen tocheck the OS issue.\n\033[40;37m" os_release=$(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 0 else 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" in redhat5|centos5|redhat6|centos6|aliyun5|aliyun6) service iptables start config_iptables ;; debian6) config_iptables ;; ubuntu10|ubuntu1204|ubuntu1210) ufwenable <<EOF y EOF 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。
2、设置iptables,限制访问
/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 --dport 8080 -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 service iptables save
以上脚本,在每次重装完系统后执行一次即可,其配置会保存至/etc/sysconfig/iptables
更详细的可以参考这篇文章 https://www.jb51.net/article/94839.htm
3、常用网络监控命令
(1) netstat -tunl:查看所有正在监听的端口
[root@AY1407041017110375bbZ ~]# netstat -tunl Active Internet connections (only servers) Proto Recv-Q Send-Q Local Address Foreign Address State tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN udp 0 0 ip:123 0.0.0.0:* udp 0 0 ip:123 0.0.0.0:* udp 0 0 127.0.0.1:123 0.0.0.0:* udp 0 0 0.0.0.0:123 0.0.0.0:*
其中123端口用于NTP服务。
(2)netstat -tunp:查看所有已连接的网络连接状态,并显示其PID及程序名称。
[root@AY1407041017110375bbZ ~]# netstat -tunp Active Internet connections (w/o servers) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 96 ip:22 221.176.33.126:52699 ESTABLISHED 926/sshd tcp 0 0 ip:34385 42.156.166.25:80 ESTABLISHED 1003/aegis_cli
根据上述结果,可以根据需要kill掉相应进程。
如:
kill -9 1003
(3)netstat -tunlp
(4)netstat常用选项说明:
-t: tcp
-u : udp
-l, --listening
Show only listening sockets. (These are omitted by default.)
-p, --program
Show the PID and name of the program to which each socket belongs.
--numeric , -n
Show numerical addresses instead of trying to determine symbolic host, port or user names.
4、修改ssh的监听端口
(1)修改 /etc/ssh/sshd_config
原有的port 22
改为port 44
(2)重启服务
/etc/init.d/sshd restart
(3)查看情况
netstat -tunl Active Internet connections (only servers) Proto Recv-Q Send-Q Local Address Foreign Address State tcp 0 0 0.0.0.0:44 0.0.0.0:* LISTEN udp 0 0 ip:123 0.0.0.0:* udp 0 0 ip:123 0.0.0.0:* udp 0 0 127.0.0.1:123 0.0.0.0:* udp 0 0 0.0.0.0:123 0.0.0.0:*