Centos 6初始化脚本

initial_centos6.sh

#!/bin/bash

#
# # sample usage
# curl -o /tmp/initial_centos6.sh https://gist.githubusercontent.com/vmlive/9994394/raw
# nohup /bin/bash /tmp/initial_centos6.sh > /tmp/initial_centos6.sh.log && rm -f /tmp/initial_centos6.sh &
#

#this script is only for CentOS 6
#check the OS
yum -y install lsb wget
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
 
 
#add the third-party repo

#add the epel
rpm -Uvh http://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm

#add the puppetlabs
rpm -Uvh http://yum.puppetlabs.com/el/6/products/x86_64/puppetlabs-release-6-10.noarch.rpm

# Turn off unnecessary services
service=($(ls /etc/init.d/))
for i in ${service[@]}; do
case $i in
cpus|ip6tables)
chkconfig $i off;;
*)
chkconfig $i on;;
esac
done
#set ulimit

#update the system and set the ntp
yum clean all
yum -y update && echo exclude=kernel* >> /etc/yum.conf
#echo '30 21 * * * /usr/sbin/ntpdate cn.pool.ntp.org > /dev/null 2>&1' >> /var/spool/cron/root

 
#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 #set sysctl
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
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 = 500000
net.core.somaxconn = 262144
net.ipv4.tcp_max_orphans = 3276800
net.ipv4.tcp_syncookies = 1
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
net.nf_conntrack_max = 25000000
net.netfilter.nf_conntrack_max = 25000000
net.netfilter.nf_conntrack_tcp_timeout_established = 180
net.netfilter.nf_conntrack_tcp_timeout_time_wait = 120
net.netfilter.nf_conntrack_tcp_timeout_close_wait = 60
net.netfilter.nf_conntrack_tcp_timeout_fin_wait = 120
vm.swappiness = 0
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
 
 
#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

# set iptables
iptables -F
iptables -X
iptables -Z
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A INPUT -p icmp -j ACCEPT
iptables -A INPUT -i lo -j ACCEPT
iptables -A INPUT -d 224.0.0.0/8 -j ACCEPT
iptables -A INPUT -p vrrp -j ACCEPT
iptables -A INPUT -m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT
iptables -A INPUT -m state --state NEW -m tcp -p tcp --dport 10050 -j ACCEPT
iptables -A INPUT -m state --state NEW -m tcp -p tcp --dport 65522 -j ACCEPT
iptables -A INPUT -p udp --sport 53 -j ACCEPT
iptables -A INPUT -p tcp --sport 53 -j ACCEPT
iptables -P INPUT DROP
#iptables -P FORWARD DROP
#iptables -P OUTPUT DROP
/etc/init.d/iptables save

cat << EOF
+-------------------------------------------------+
|               optimizer is done                               |
|   it's recommond to restart this server !             |
+-------------------------------------------------+
EOF