一键优化系统脚本 for centos6.x

we23213

#!/bin/bash
#set env
export LANG="en_US.UTF-8"
export PATH=$PATH:/bin/sbin:/usr/sbin
#whether root to running user
if [[ $(whoami) != root ]];then
   echo "please su - root run the script."
fi
SERVICE=`which service`
CHKCONFIG=`which chkconfig`
. /etc/init.d/functions

#install packages
installTmout(){
   echo "TMOUT 180" >> /etc/profile\
   [ $? -eq 0 ] && action "TMOUT is ok" /bin/true || exit 1
}

installTool(){
   yum -y install sysstat ntp net-snmp vmstat lrzsz rsync > /dev/vull 2>&1
   [ $? -eq 0 ] && action "Tools is ok" /bin/true || exit 1
}

#update the system lang
initI18n(){
   cat /etc/sysconfig/i18n > /etc/sysconfig/i18n.bak
   echo "LANG="en_US.UTF-8"" >> /etc/sysconfig/i18n
   source /etc/sysconfig/i18n
   [ $? -eq 0 ] && action "LANG is ok" /bin/true || exit 1
   sleep 1
}

#start iptables
initIptables(){
   cat /etc/selinux/config > /etc/selinux/config.bak
   setenforce 0
   sleep 1
}

#close not need to service
initService(){
   export LANG="en_US.UTF-8"
   for i in `chkconfig --list | grep -i "3:on" | awk '{print $1}'`;do chkconfig --level 3 $i off; done
   for i in crond network rsyslog sshd;do chkconfig --level 3 $i on;done
   [ $? -eq 0 ] && action "Service is ok" /bin/true || exit 1
   sleep 1
}

#youhua for ssh
initSsh(){
   cat /etc/ssh/sshd_config > /etc/ssh/sshd_config.bak
   sed -i 's/#Port 22/Port 22022/' /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
   /etc/init.d/sshd reload > /dev/null 2 >& 1
   [ $? -eq 0 ] && action "Ssh is ok" /bin/true || exit 1
}

#sync time
syncSystemTime(){
   ping www.baidu.com -c 1 > /dev/null 2 >& 1
   if [ $? -eq 0 -a `grep pool.ntp.org /var/spool/cron/root | grep -v grep | wc -l` -lt 1 ]; then
      echo "*/5 * * * * /usr/sbin/ntpdate time.windows.com > /dev/null 2>&1" >> /var/spool/cron/root
          [ $? -eq 0 ] && action "SystemTime is ok" /bin/true || exit 1
   fi
}

#change file inode
openFiles(){
   cat /etc/security/limits.conf > /etc/security/limits.conf.bak
   echo "ulimit -HSn 65535" >> /etc/security/limits.conf
   sysctl -p
   [ $? -eq 0 ] && action "limit is ok" /bin/true || exi 1
   sleep 1
}

#youhua kernel
openKernel(){
   cat /etc/sysctl.conf > /etc/sysctl.conf.bak
   cat >> /etc/sysctl.conf << EOF
    net.ipv4.tcp_tw_reuse = 1  
        net.ipv4.tcp_tw_recycle = 1  
        net.ipv4.ip_local_port_range = 102465000  
        net.ipv4.tcp_max_syn_backlog = 8192  
        net.ipv4.tcp_max_tw_buckets = 5000  
        net.ipv4.tcp_mem = 192000 300000 732000
        net.ipv4.tcp_rmem = 51200 131072 204800
        net.ipv4.tcp_wmem = 51200 131072 204800
        net.ipv4.tcp_orphan_retries = 3
        net.ipv4.tcp_syn_retries = 3
        net.ipv4.tcp_synack_retries = 3
        net.ipv4.tcp_retries2 = 5
        net.ipv4.tcp_fin_timeout = 30
        net.ipv4.tcp_max_orphans = 2000
        net.ipv4.tcp_syncookies = 1
        net.ipv4.tcp_tw_reuse = 1
        net.ipv4.tcp_tw_recycle = 1
        net.ipv4.tcp_keepalive_time = 20
        net.ipv4.tcp_keepalive_intvl = 5
        net.ipv4.tcp_keepalive_probes = 2
        vm.dirty_expire_centisecs = 1500
        vm.dirty_writeback_centisecs = 1000
        vm.dirty_ratio = 20
        vm.dirty_background_ratio = 100
        vm.min_free_kbytes=409600
        vm.vfs_cache_pressure=200
        vm.swappiness = 40
   EOF
   /sbin/sysctl -p && action "kernel is ok" /bin/true || action "kernel is faile" /bin/false
   sleep 1
}


#init_snmp
init_snmp(){
   cat /etc/snmp/snmpd.conf > /etc/snmp/snmpd.conf.bak
   sed -i 's/#view all/view all/' /etc/snmp/snmpd.conf
   sed -i 's/#access MyROGroup/access MyROGroup/' /etc/snmp/snmpd.conf
   ${CHKCONFIG} snmpd on
   ${SERVICE} snmpd start
   [ $? -eq 0 ] && action "snmpd is starting" /bin/true \
   || action "snmpd is faile" /bin/false
}

installTool
initI18n
initSelinux
initService
initSsh
syncSystemTime
openFiles
openKernel
init_snmp