CentOS 6 系统优化 Shell 脚本

CentOS 已经发布了6.2版了,现在已经可以用在生产环境了,新版本的内核也能更好的利用硬件.写了一个脚本,用来初始化系统环境,现在分享出来,你可以根据自己的需要,对脚本进行相应的修改.
脚本的内容如下:

#!/bin/bash
#author suzezhi
#this script is only for CentOS 6
#check the OS
platform=`uname -i`
if [ $platform != "x86_64" ];then
echo "this script is only for 64bit Operating System !"
exit 1
fi
echo "the platform is ok"
version=`lsb_release -r |awk '{print substr($2,1,1)}'`
if [ $version != 6 ];then
echo "this script is only for CentOS 6 !"
exit 1
fi
cat  EOF
+---------------------------------------+
| your system is CentOS 6 x86_64 |
| start optimizing....... |
+---------------------------------------
EOF
#make the 163.com as the default yum repo
mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup
wget http://mirrors.163.com/.help/CentOS6-Base-163.repo -O /etc/yum.repos.d/CentOS-Base.repo
#add the third-party repo
#add the epel
rpm -Uvh http://download.Fedora.RedHat.com/pub/epel/6/x86_64/epel-release-6-5.noarch.rpm
rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-6
#add the rpmforge
rpm -Uvh http://packages.sw.be/rpmforge-release/rpmforge-release-0.5.2-2.el6.rf.x86_64.rpm
rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY-rpmforge-dag
#update the system and set the ntp
yum clean all
yum -y update glibc*
yum -y update yum* rpm* python*
yum -y update
yum -y install ntp
echo "* 4 * * * /usr/sbin/ntpdate 210.72.145.44  /dev/null 2&1"  /var/spool/cron/root
service crond restart
#set the file limit
echo "ulimit -SHn 102400"  /etc/rc.local
cat  /etc/security/limits.conf  EOF
* soft nofile 65535
* hard nofile 65535
EOF
#set the control-alt-delete to guard against the miSUSE
sed -i 's#exec /sbin/shutdown -r now##exec /sbin/shutdown -r now#' /etc/init/control-alt-delete.conf
#disable selinux
sed -i 's/SELINUX=enforcing/SELINUX=disabled/' /etc/selinux/config
#set ssh
sed -i 's/^GSSAPIAuthentication yes$/GSSAPIAuthentication no/' /etc/ssh/sshd_config
sed -i 's/#UseDNS yes/UseDNS no/' /etc/ssh/sshd_config
service sshd restart
#tune kernel parametres
cat  /etc/sysctl.conf  EOF
net.ipv4.tcp_fin_timeout = 1
net.ipv4.tcp_keepalive_time = 1200
net.ipv4.tcp_mem = 94500000 915000000 927000000
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_timestamps = 0
net.ipv4.tcp_synack_retries = 1
net.ipv4.tcp_syn_retries = 1
net.ipv4.tcp_tw_recycle = 1
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.core.wmem_default = 8388608
net.core.rmem_default = 8388608
EOF
/sbin/sysctl -p
#define the backspace button can erase the last character typed
echo 'stty erase ^H'  /etc/profile
echo "syntax on"  /root/.vimrc
#stop some crontab
mkdir /etc/cron.daily.bak
mv /etc/cron.daily/makewhatis.cron /etc/cron.daily.bak
mv /etc/cron.daily/mlocate.cron /etc/cron.daily.bak
chkconfig bluetooth off
chkconfig cups off
chkconfig ip6tables off
#disable the ipv6
cat  /etc/modprobe.d/ipv6.conf  EOFI
alias net-pf-10 off
options ipv6 disable=1
EOFI
echo "NETWORKING_IPV6=off"  /etc/sysconfig/network
cat  EOF
+-------------------------------------------------+
| optimizer is done |
| it's recommond to restart this server ! |
+-------------------------------------------------+
EOF

对脚本的内容做一下说明:

先对系统进行判断,如果是Cent OS 64位,就继续运行.
先将系统的安装源设置为网易的(网易的安装源算是国内比较稳定的)
安装epel的源和rpmforge的源,利用第三方的源来让yum安装起来更方便
更新软件
设置为每天凌晨四点进行时间同步(跟国家授时中心的服务器进行时间同步)
将系统同时打开的文件个数增大
将ctrl ALT delete键进行屏蔽,防止误操作的时候服务器重启
关闭SELinux
禁用GSSAPI来认证,也禁用DNS反向解析,加快SSH登陆速度
优化一些内核参数
调整删除字符的按键为backspace(某些系统默认是delete)
打开vim的语法高亮
取消生成whatis数据库和locate数据库
关闭没用的服务
关闭IPv6