PS：本Shell脚本是在和【】学习后，然后工作实践后的优化脚本，主要用于新安装Linux服务器系统的初始化安全设置，具体包括：修改系统Yum源，设置字符编码，关闭防火墙和Selinux,关闭不必要系统服务，关闭IPV6模块，调整系统打开文件数，优化系统内核等。大家可以根据自己的实际情况做出修改，用于生产环境前请先做好测试，已经在CentOS 5.8 i386下通过。
| #!/bin/bash # # Script Name: initSystem.sh # Description: setup linux system init. # Author: 300second - 51cto.com # Date: 2012-10-30 # #set env export PATH=$PATH:/bin:/sbin:/usr/sbin export LANG="zh_CN.GB18030" #require root to run this script. if [[ "$(whoami)" != "root" ]]; then echo "Please run this script as root." >&2 exit 1 fi #define cmd var SERVICE=`which service` CHKCONFIG=`which chkconfig` #Source function library. . /etc/init.d/functions #Modify the system yum source //修改系统Yum源 initYum() { cat << EOF +--------------------------------------------------------------+ +------ Welcome to Modify the system yum source. ------+ +--------------------------------------------------------------+ EOF cd /etc/yum.repos.d/ \cp CentOS-Base.repo CentOS-Base.repo.ori.$(date +%F) ping -c 1 baidu.com >/dev/null [ ! $? -eq 0 ] && echo $"Networking not configured - exiting" && exit 1 wget --quiet -o /dev/null \cp CentOS-Base-sohu.repo CentOS-Base.repo echo "Modify the system yum source.------->OK" sleep 3 } #Set the character encoding //设置字符编码 initI18n() { cat << EOF +--------------------------------------------------------------+ +------ Welcome to Set the character encoding. ------+ +--------------------------------------------------------------+ EOF echo "#set LANG="zh_cn.gb18030"" \cp /etc/sysconfig/i18n /etc/sysconfig/i18n.$(date +%F) sed -i 's#LANG="en_US.UTF-8"#LANG="zh_CN.GB18030"#' /etc/sysconfig/i18n source /etc/sysconfig/i18n grep LANG /etc/sysconfig/i18n echo "Set the character encoding.------->OK" sleep 3 } #Close the firewall and Selinux //关闭防火墙和Selinux initFirewall() { cat << EOF +--------------------------------------------------------------+ +------ Welcome to Close the firewall and Selinux. ------+ +--------------------------------------------------------------+ EOF \cp /etc/selinux/config /etc/selinux/config.`date +"%Y-%m-%d_%H-%M-%S"` /etc/init.d/iptables stop chkconfig iptables off sed -i 's/SELINUX=enable/SELINUX=disabled/' /etc/selinux/config setenforce 0 /etc/init.d/iptables status grep SELINUX=disabled /etc/selinux/config echo "Close the firewall and Selinux.------->OK" sleep 3 } #Close unnecessary system service //关闭不必要系统服务 initService() { cat << EOF +--------------------------------------------------------------+ +------ Welcome to Close unnecessary system service . ------+ +--------------------------------------------------------------+ EOF export LANG="en_US.UTF-8" for i in `chkconfig --list |grep 3:on|awk '{print $1}'`;do chkconfig --level 3 $i off;done for i in crond network sshd syslog;do chkconfig --level 3 $i on;done export LANG="zh_CN.GB18030" echo "Close unnecessary system service.------>OK" sleep 3 } #Set the sshConfig banned root login //设置sshConfig,禁止root登录 initSsh() { cat << EOF +--------------------------------------------------------------+ +------ Welcome to Set the sshConfig banned root login. ------+ +--------------------------------------------------------------+ EOF \cp /etc/ssh/sshd_config /etc/ssh/sshd_config.`date +"%Y-%m-%d_%H-%M-%S"` sed -i 's%#Port 22%Port 52113%' /etc/ssh/sshd_config sed -i 's%#PermitRootLogin yes%PermitRootLogin no%' /etc/ssh/sshd_config sed -i 's%#PermitEmptyPasswords no%PermitEmptyPasswords no%' /etc/ssh/sshd_config sed -i 's%#UseDNS yes%UseDNS no' /etc/ssh/sshd_config egrep "UseDNS|52113|RootLogin|EmptyPass" /etc/ssh/sshd_config /etc/init.d/sshd reload echo "Set the sshConfig banned root login.------>OK" sleep 3 } #Disable ctrlaltdel three key to reboot system //禁止ctrl+alt+del三个键重启系统 initSafe() { cat << EOF +--------------------------------------------------------------+ +-- Welcome to Disable ctrlaltdel three key to reboot system.--+ +--------------------------------------------------------------+ EOF \cp /etc/inittab /etc/inittab.`date +"%Y-%m-%d_%H-%M-%S"` sed -i "s/ca::ctrlaltdel:\/sbin/shutdown -t3 -r now/#ca::ctrlaltdel:\/sbin/shutdown -t3 -r now/" /etc/inittab /sbin/init q echo "Disable ctrlaltdel three key to reboot system.------>OK" sleep 3 } #Add users and set permissions in sudo //添加SA用户并设置sudo权限 initAddUser() { cat << EOF +--------------------------------------------------------------+ +------Welcome to Add users and set permissions in sudo.------+ +--------------------------------------------------------------+ EOF datetmp=`date +"%Y-%m-%d_%H-%M-%S"` \cp /etc/sudoers /etc/sudoers.${datetmp} saUserArr=(test test1 test2) groupadd -g 901 sa for((i=0;i<${#saUserArr[@]};i++)) do #add user //添加用户 useradd -g sa -u 90${i} ${saUserArr[$i]} #set password //设置密码 echo "${saUserArr[$i]}123"|passwd ${saUserArr[$i]} --stdin #set permissions //设置sudo权限 [ $(grep "${saUserArr[$i]} ALL=(ALL) NOPASSWD: ALL" /etc/sudoers|wc -l) -le 0 ] &&echo "${saUserArr[$i]} ALL=(ALL) NOPASSWD: ALL" >>/etc/sudoers [ `grep "\%sa" /etc/sudoers|grep -v grep |wc -l` -ne 1 ] && \ echo "%sa ALL=(ALL) NOPASSWD: ALL" >>/etc/sudoers done /usr/sbin/visudo -c [ $? -ne 0 ] && /bin/cp /etc/sudoers.${datetmp} /etc/sudoers && echo $"Sudoers not configured - exiting" && exit 1 echo "Add users and set permissions in sudo.------>OK" sleep 3 } #Adjust the number of open files //调整系统打开文件数 initOpenFiles() { cat << EOF +--------------------------------------------------------------+ +------ Welcome to Adjust the number of open files. ------+ +--------------------------------------------------------------+ EOF \cp /etc/security/limits.conf /etc/security/limits.conf.`date +"%Y-%m-%d_%H-%M-%S"` sed -i ' /# End of file/i\*\t\t-\tnofile\t\t65535' /etc/security/limits.conf ulimit -HSn 65535 echo "ulimit -HSn 65535" >> /etc/rc.local echo "Adjust the number of open files.------>OK" sleep 3 } #Set system time synchronization //设置系统同步时间 initSysTime() { cat << EOF +--------------------------------------------------------------+ +------ Welcome to Set system time synchronization. ------+ +--------------------------------------------------------------+ EOF yum -y install ntp >>/dev/null 2>&1 ntpdate time.windows.com echo "*/5 * * * * /usr/sbin/ntpdate time.windows.com >/dev/null 2>&1" >>/var/spool/cron/root echo "Set system time synchronization.------>OK" sleep 3 } #Optimization of system kernel //优化系统内核 initKernel() { cat << EOF +--------------------------------------------------------------+ +------ Welcome to Optimization of system kernel. ------+ +--------------------------------------------------------------+ EOF \cp /etc/sysctl.conf /etc/sysctl.conf.`date +"%Y-%m-%d_%H-%M-%S"` cat>>/etc/sysctl.conf<<EOF net.ipv4.tcp_timestamps = 0 net.ipv4.tcp_synack_retries = 2 net.ipv4.tcp_syn_retries = 2 net.ipv4.tcp_mem = 94500000 915000000 927000000 net.ipv4.tcp_max_orphans = 3276800 net.core.wmem_default = 8388608 net.core.rmem_default = 8388608 net.core.rmem_max = 16777216 net.core.wmem_max = 16777216 net.ipv4.tcp_rmem = 4096 87380 16777216 net.ipv4.tcp_wmem = 4096 87380 16777216 net.core.netdev_max_backlog = 32768 net.core.somaxconn = 32768 net.ipv4.tcp_syncookies = 1 net.ipv4.tcp_tw_reuse = 1 net.ipv4.tcp_tw_recycle = 1 net.ipv4.tcp_fin_timeout = 1 net.ipv4.tcp_keepalive_time = 600 net.ipv4.tcp_max_syn_backlog = 65535 net.ipv4.ip_local_port_range = 1024 65535 EOF /sbin/sysctl -p echo "Optimization of system kernel.------>OK" sleep 3 } #Installation system tools //安装系统工具 initTool() { cat << EOF +--------------------------------------------------------------+ +------ Welcome to Installation system tools. ------+ +------ <sysstat ntp net-snmp lrzsz rsync> ------+ +--------------------------------------------------------------+ EOF yum -y install sysstat ntp net-snmp lrzsz rsync >/dev/null 2>&1 echo "Installation system tools.------->OK" sleep 3 } #Prohibit the use of IPV6 //禁止使用IPV6 initIPV6() { cat << EOF +--------------------------------------------------------------+ +------ Welcome to Prohibit the use of IPV6. ------+ +--------------------------------------------------------------+ EOF \cp /etc/modprobe.conf /etc/modprobe.conf.`date +"%Y-%m-%d_%H-%M-%S"` echo "alias net-pf-10 off" >> /etc/modprobe.conf echo "alias ipv6 off" >> /etc/modprobe.conf echo "Prohibit the use of IPV6.------>OK" sleep 3 } AStr="修改系统Yum源，设置字符编码，关闭防火墙和Selinux,关闭不必要系统服务" BStr="配置sshConfig，修改默认端口22->52113和禁止root登录" CStr="禁止Ctrl+Alt+Del三个键重启系统" DStr="添加SA用户并设置sudo权限" EStr="调整系统打开文件数" FStr="设置系统同步时间" GStr="优化系统内核" HStr="安装系统工具" IStr="禁止使用IPV6" JStr="一键初始化" echo "+--------------------------------------------------------------+" echo "+-----------------欢迎对系统进行初始化安全设置！---------------+" echo "A：${AStr}" echo "B：${BStr}" echo "C：${CStr}" echo "D：${DStr}" echo "E：${EStr}" echo "F：${FStr}" echo "G：${GStr}" echo "H：${HStr}" echo "I：${IStr}" echo "J：${JStr}" echo "+--------------------------------------------------------------+" echo "注意：如果没有选择初始化选项，20秒后将自动选择一键初始化安装！" echo "+--------------------------------------------------------------+" option="-1" read -n1 -t20 -p "请选择初始化选项【A-B-C-D-E-F-G-H-I-J】:" option flag1=$(echo $option|egrep "\-1"|wc -l) flag2=$(echo $option|egrep "[A-Ja-j]"|wc -l) if [ $flag1 -eq 1 ];then option="K" elif [ $flag2 -ne 1 ];then echo -e "\n\n请重新运行脚本，输入从A--->J的字母！" exit 1 fi echo -e "\n你选择的选项是：$option\n" echo "5秒之后开始安装 ......" sleep 5 case $option in A|a) initYum initI18n initFirewall initService ;; B|b) initSsh ;; C|c) initSafe ;; D|d) initAddUser ;; E|e) initOpenFiles ;; F|f) initSysTime ;; G|g) initKernel ;; H|h) initTool ;; I|i) initIPV6 ;; J|j) initYum initI18n initFirewall initService initSsh initSafe initAddUser initOpenFiles initSysTime initKernel initTool initIPV6 ;; *) echo "请输入从A--->J的字母，谢谢！" exit ;; esac |