CentOS6 x86_64最小化安装优化脚本

#!/bin/bash
#centos6.8 x86_64系统最小化安装优化脚本
#系统基础优化，建议以root运行

if [ $USER != "root" ];then
    echo "需要使用sudo运行此脚本"
    exit 1
fi

yum -y intall wget
cd /usr/local/src
wget http://mirrors.163.com/.help/CentOS6-Base-163.repo
cd /etc/yum.repos.d/
mv CentOS-Base.repo CentOS-Base.repo.bak
cp /usr/local/src/CentOS6-Base-163.repo ./CentOS-Base.repo
yum clean all #清除yum缓存
yum makecache #重建缓存
yum -y update
cd /usr/local/src
#添加epel外部扩展源
wget http://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
rpm -ivh epel-release-6-8.noarch.rpm

#安装gcc ，sysstat等工具
yum -y install gcc gcc-c++ vim-enhanced unzip unrar sysstat

#配置ntp自动对时
yum -y install ntp
echo "01 01 * * *  /usr/sbin/ntpdate ntp.api.bz >> /dev/null 2>&1 " >> /etc/crontab
/usr/sbin/ntpdate ntp.api.bz
service crond restart

#配置文件的ulimit值
ulimit -SHn 65534
echo "ulimit -SHn 65534" >> /etc/rc.local

cat >> /etc/security/limits.conf << EOF
*           soft    nofile      65535
*           hard    nofile      65535
EOF

#基础系统内核优化
cat >> /etc/sysctl.conf << EOF
net.ipv4.tcp_syncookies = 1                
net.ipv4.tcp_syn_retries = 1
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_tw_reuse = 1 
net.ipv4.tcp_fin_timeout = 1
net.ipv4.tcp_keepalive_time = 1200
net.ipv4.tcp_local_port_range = 10000 65535 
net.ipv4.tcp_max_syn_backlog = 16384
net.ipv4.tcp_max_tw_buckets = 36000 
net.ipv4.route.gc_timeout = 100
net.core.somaxconn = 16384
net.core.netdev_max_backlog = 16384
net.ipv4.tcp_max_orphans = 16384

EOF
/sbin/sysctl -p


#关闭selinux
sed -i 's/SELINUX=enforcing/SELINUX=disabled/' /etc/selinux/config
setenforce 0
#关闭itables
service iptables stop
chkconfig iptables off

#ssh配置优化
sed -i 's/#PermitEmptyPasswords no/PermitEmptyPasswords no/g' /etc/ssh/sshd_config
sed -i "s/#UseDNS yes/UseDNS no/g" /etc/ssh/sshd_config
service sshd restart

#禁用基于ipv6 网络
chkconfig ip6tables off


#vim 基础语法优化
cat >> /root/.vimrc << EOF
set nu
set ruler
set shiftwidth=4
set tabstop=4
set expandtab
set cindent
set autoindent
set mouse=v
syntax on
EOF

#精简开机启动服务，安装最小化服务的机器初始只留 cron|network|rsyslog|sshd 四个服务
for i in `chkconfig --list | grep 3:on | awk '{print $1}'`;do chkconfig --level 3 $i off;done

for CURSRV in crond rsyslog sshd network;do chkconfig --level 3 $CURSRV on;done

#重启服务器
reboot