Linux系统初始化Shell脚本

    此脚本用于新装CentOS的相关配置工作，比如禁掉iptable和SElinux及ipv6，优化系统内核，停掉一些没必要启动的系统服务等。此脚本尤其适全大批新安装的CentOS 5.X系列的服务器，脚本代码如下所示（此脚本在Centos5.5_x64下已通过）：

#!/bin/bash # Created by kerryhu # MAIL:king_819@163.com # BLOG:http://kerry.blog.51cto.com cat << EOF +————————————————————–+ |         === Welcome to Centos System init ===                | +————————————————————–+ +————————–by kerry—————————-+ EOF #set ntp yum -y install ntp echo “* 3 * * * /usr/sbin/ntpdate 210.72.145.44 > /dev/null 2>&1” >> /etc/crontab service crond restart #set ulimit echo “ulimit -SHn 102400″ >> /etc/rc.local #set locale #true > /etc/sysconfig/i18n #cat >>/etc/sysconfig/i18n<<EOF #LANG=”zh_CN.GB18030″ #SUPPORTED=”zh_CN.GB18030:zh_CN:zh:en_US.UTF-8:en_US:en” #SYSFONT=”latarcyrheb-sun16″ #EOF #set sysctl true > /etc/sysctl.conf cat >> /etc/sysctl.conf << EOF net.ipv4.ip_forward = 0 net.ipv4.conf.default.rp_filter = 1 net.ipv4.conf.default.accept_source_route = 0 kernel.sysrq = 0 kernel.core_uses_pid = 1 net.ipv4.tcp_syncookies = 1 kernel.msgmnb = 65536 kernel.msgmax = 65536 kernel.shmmax = 68719476736 kernel.shmall = 4294967296 net.ipv4.tcp_max_tw_buckets = 6000 net.ipv4.tcp_sack = 1 net.ipv4.tcp_window_scaling = 1 net.ipv4.tcp_rmem = 4096 87380 4194304 net.ipv4.tcp_wmem = 4096 16384 4194304 net.core.wmem_default = 8388608 net.core.rmem_default = 8388608 net.core.rmem_max = 16777216 net.core.wmem_max = 16777216 net.core.netdev_max_backlog = 262144 net.core.somaxconn = 262144 net.ipv4.tcp_max_orphans = 3276800 net.ipv4.tcp_max_syn_backlog = 262144 net.ipv4.tcp_timestamps = 0 net.ipv4.tcp_synack_retries = 1 net.ipv4.tcp_syn_retries = 1 net.ipv4.tcp_tw_recycle = 1 net.ipv4.tcp_tw_reuse = 1 net.ipv4.tcp_mem = 94500000 915000000 927000000 net.ipv4.tcp_fin_timeout = 1 net.ipv4.tcp_keepalive_time = 1200 net.ipv4.ip_local_port_range = 1024 65535 EOF /sbin/sysctl -p echo “sysctl set OK!!” #close ctrl+alt+del sed -i “s/ca::ctrlaltdel:/sbin/shutdown -t3 -r now/#ca::ctrlaltdel:/sbin/shutdown -t3 -r now/” /etc/inittab #set purview chmod 600 /etc/passwd chmod 600 /etc/shadow chmod 600 /etc/group chmod 600 /etc/gshadow #disable ipv6 cat << EOF +————————————————————–+ |         === Welcome to Disable IPV6 ===                      | +————————————————————–+ EOF echo “alias net-pf-10 off” >> /etc/modprobe.conf echo “alias ipv6 off” >> /etc/modprobe.conf /sbin/chkconfig –level 35 ip6tables off echo “ipv6 is disabled!” #disable selinux sed -i ‘/SELINUX/s/enforcing/disabled/’ /etc/selinux/config echo “selinux is disabled,you must reboot!” #vim sed -i “8 s/^/alias vi=’vim’/” /root/.bashrc echo ‘syntax on’ > /root/.vimrc #zh_cn sed -i -e ‘s/^LANG=.*/LANG=”en”/’   /etc/sysconfig/i18n #init_ssh ssh_cf=”/etc/ssh/sshd_config” sed -i -e ’74 s/^/#/’ -i -e ’76 s/^/#/’ $ssh_cf #sed -i “s/#Port 22/Port 65535/” $ssh_cf sed -i “s/#UseDNS yes/UseDNS no/” $ssh_cf #client sed -i -e ’44 s/^/#/’ -i -e ’48 s/^/#/’ $ssh_cf service sshd restart echo “ssh is init is ok…………..” #chkser #tunoff services #——————————————————————————– cat << EOF +————————————————————–+ |         === Welcome to Tunoff services ===                   | +————————————————————–+ EOF #——————————————————————————— for i in `ls /etc/rc3.d/S*` do               CURSRV=`echo $i|cut -c 15-` echo $CURSRV case $CURSRV in           crond | irqbalance | microcode_ctl | network | random | sshd | syslog | local )       echo “Base services, Skip!”       ;;       *)           echo “change $CURSRV to off”           chkconfig –level 235 $CURSRV off           service $CURSRV stop       ;; esac done echo “service is init is ok…………..”