linux系统初始化

#!/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" ]( "$(whoami)" != "root" .md); 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 $"Networking not configured - exiting" && exit 1
wget --quiet -o /dev/null http://mirrors.sohu.com/help/CentOS-Base-sohu.repo
\cp CentOS-Base-sohu.repo CentOS-Base.repo
echo "Modify the system yum source.------->OK"
sleep 3
}
#Set the character encoding  //设置字符编码
initI18n() {
cat << EOF
+--------------------------------------------------------------+
+------       Welcome to Set the character encoding.     ------+
+--------------------------------------------------------------+
EOF
echo "#set LANG="zh_cn.gb18030""
\cp /etc/sysconfig/i18n /etc/sysconfig/i18n.$(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<${#saUserArr![pic](@)};i++))
do
#add user //添加用户
useradd -g sa -u 90${i} ${saUserArr![pic]($i)}
#set password //设置密码
echo "${saUserArr![pic]($i)}123"|passwd ${saUserArr![pic]($i)} --stdin
#set permissions //设置sudo权限
[ $(grep "${saUserArr![pic]($i)} ALL=(ALL) NOPASSWD: ALL" /etc/sudoers|wc -l) -le 0 ] &&echo "${saUserArr![pic]($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 "![pic](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