系统下载
可以使用最小化的,也可以使用dvd版(CentOS-6.7-x86_64-bin-DVD1.iso),其中dvd版方便安装过程中选包.
一. 系统安装
1,时区选择
2,磁盘分区
boot | 保持默认200M |
swap | 1024M |
/ | 剩余空间 |
备注: 其中3个分区都force be a primary partion |
注意: raid之后的空间超过2T,fdisk就无法使用.改用parted
3.安装选包
Base
Compatibility libraries
Debugging Tools
Development tools
1、根据经验,选择安装包时应该按最小化原则,即不需要的或者不确定是否需要的就不安装,这样可以最大程度上确保系统安全。
2、如果安装过程落了部分包组或者其他伙伴安装时没选,再安装后可以按如下方式补上安装时未安装的包组:
yum groupinstall "Compatibility libraries" "Base" "Development tools"
yum groupinstall "debugging Tools" "Dial-up Networking Support"
可以通过yum groupinfo 包组查看具体安装的组件。
3、下面安装6.5后登陆系统的时候查看选包的情况:
yum grouplist: #前4个都需要有
Installed Groups:
Base
Compatibility libraries
Debugging Tools
Development tools
E-mail server
Graphical Administration Tools
Hardware monitoring utilities
Legacy UNIX compatibility
Networking Tools
Performance Tools
Perl Support
Scientific support
Security Tools
*可以看到除了我们选择的外,系统还是默认安装了一些额外的软件包组。
注意:不要使用yum的删除功能删除软件,会删除相关依赖,导致意外问题。
如果centos6系统已安装,如何补救没有安装的包?以及初始化安装时选包注意事项.
4.linux忘记密码处理(进单用户[启动级别为1]的模式去处理)
开机按e键,
输入户single,单用户模式启动(级别)
$ cat /etc/inittab
...
# 0 - halt (Do NOT set initdefault to this)
# 1 - Single user mode
# 2 - Multiuser, without NFS (The same as 3, if you do not have networking)
# 3 - Full multiuser mode
# 4 - unused
# 5 - X11
# 6 - reboot (Do NOT set initdefault to this)
passwd root # 更新密码并重启即可.
5.centos6-系统优化
优化小结: 一清: 定时清理日志/var/spool/clientsqueue
一精: 精简开机启动服务
一增: 增大文件描述符
两优: linux内核参数的优化、yum源优化
四设:设置系统的字符集、设置ssh登录限制、设置开机的提示信息与内核信息、设置block的大小
七其他:文件系统优化、sync数据同步写入磁盘、不更新时间戳、锁定系统关键文件、时间同步、sudo集权管理、关闭防火墙和selinux
本文 centos 6.5 优化 的项有18处:
1、CentOS6.5最小化安装后启动网卡
2、ifconfig查询IP进行SSH链接
3、更新系统源并且升级系统
4、系统时间更新和设定定时任
5、修改ip地址、网关、主机名、DNS
6、关闭seLinux,清空iptables
7、创建普通用户并进行sudo授权管理
8、修改SSH端口号和屏蔽root账号远程登陆
9、锁定关键文件系统(禁止非授权用户获得权限)
10、精简开机自启动服务
11、调整系统文件描述符大小
12、设置系统字符集
13、清理登陆的时候显示的系统及内核版本
14、内核参数优化
15、定时清理/var/spool/clientmqueue
16、删除不必要的系统用户和群组
17、关闭重启ctl-alt-delete组合键
18、设置一些全局变量
#!/bin/sh
################################################
# this script is created by lanny
# version:1.2
################################################
#Source function library.
. /etc/init.d/functions
#date
DATE=`date +"%Y-%m-%d %H:%M:%S"`
#ip
IPADDR=IPADDR=`ifconfig eth0|sed -n '2p'|awk -F ":" '{print $2}'|awk '{print $1}'`
#hostname
HOSTNAME=`hostname -s`
#user
USER=`whoami`
#disk_check
DISK_SDA=`df -h |grep -w "/" |awk '{print $5}'`
#cpu_average_check
cpu_uptime=`cat /proc/loadavg|awk '{print $1,$2,$3}'`
#set LANG
export LANG=zh_CN.UTF-8
#Require root to run this script.
uid=`id | cut -d\( -f1 | cut -d= -f2`
if [ $uid -ne 0 ];then
action "Please run this script as root." /bin/false
exit 1
fi
#"stty erase ^H"
\cp /root/.bash_profile /root/.bash_profile_$(date +%F)
erase=`grep -wx "stty erase ^H" /root/.bash_profile |wc -l`
if [ $erase -lt 1 ];then
echo "stty erase ^H" >>/root/.bash_profile
source /root/.bash_profile
fi
#Config Yum CentOS-Bases.repo
configYum(){
echo "================更新为国内YUM源=================="
cd /etc/yum.repos.d/
\cp CentOS-Base.repo CentOS-Base.repo.$(date +%F)
ping -c 2 mirrors.aliyun.com >/dev/null
if [ $? -eq 0 ];then
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-6.repo
wget -O /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-6.repo
yum clean all && yum makecache
else
echo "无法连接网络。"
exit $?
fi
action "配置国内aliyun YUM完成" /bin/true
echo "================================================="
echo ""
sleep 2
}
#install tools
initTools(){
echo "#####install tools#####"
yum install lrzsz ntpdate sysstat dos2unix wget telnet vim-enhanced -y
yum groupinstall base -y
yum groupinstall core -y
yum groupinstall development libs -y
yum groupinstall development tools -y
echo "install toos complete."
sleep 1
}
initVim(){
cat >>/etc/vimrc<<EOF
set nu
set cursorline
set nobackup
set ruler
set autoindent
set vb t_vb=
set ts=4
set expandtab
EOF
source /etc/vimrc
}
#Charset zh_CN.UTF-8
initI18n(){
echo "================更改为中文字符集================="
\cp /etc/sysconfig/i18n /etc/sysconfig/i18n.$(date +%F)
echo "LANG="zh_CN.UTF-8"" >/etc/sysconfig/i18n
source /etc/sysconfig/i18n
echo '#cat /etc/sysconfig/i18n'
grep LANG /etc/sysconfig/i18n
action "更改字符集zh_CN.UTF-8完成" /bin/true
echo "================================================="
echo ""
sleep 2
}
#Close Selinux and Iptables
initFirewall(){
echo "============禁用SELINUX及关闭防火墙=============="
\cp /etc/selinux/config /etc/selinux/config.$(date +%F)
/etc/init.d/iptables stop
sed -i 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/selinux/config
setenforce 0
/etc/init.d/iptables status
echo '#grep SELINUX=disabled /etc/selinux/config '
grep SELINUX=disabled /etc/selinux/config
echo '#getenforce '
getenforce
action "禁用selinux及关闭防火墙完成" /bin/true
echo "================================================="
echo ""
sleep 2
}
#Init Auto Startup Service
initService(){
echo "===============精简开机自启动===================="
export LANG="en_US.UTF-8"
for A in `chkconfig --list |grep 3:on |awk '{print $1}' `;do chkconfig $A off;done
for B in rsyslog network sshd crond;do chkconfig $B on;done
echo '+--------which services on---------+'
chkconfig --list |grep 3:on
echo '+----------------------------------+'
export LANG="zh_CN.UTF-8"
action "精简开机自启动完成" /bin/true
echo "================================================="
echo ""
sleep 2
}
#Change sshd default port and prohibit user root remote login.
initSsh(){
echo "========修改ssh默认端口禁用root远程登录=========="
\cp /etc/ssh/sshd_config /etc/ssh/sshd_config.$(date +%F)
sed -i 's/#Port 22/Port 52000/g' /etc/ssh/sshd_config
sed -i 's/#PermitEmptyPasswords no/PermitEmptyPasswords no/g' /etc/ssh/sshd_config
sed -i 's/#PermitRootLogin yes/PermitRootLogin no/g' /etc/ssh/sshd_config
sed -i 's/#UseDNS yes/UseDNS no/g' /etc/ssh/sshd_config
echo '+-------modify the sshd_config-------+'
echo 'Port 52000'
echo 'PermitEmptyPasswords no'
echo 'PermitRootLogin no'
echo 'UseDNS no'
echo '+------------------------------------+'
/etc/init.d/sshd reload && action "修改ssh默认参数完成" /bin/true || action "修改ssh参数失败" /bin/false
echo "================================================="
echo ""
sleep 2
}
#time sync
syncSysTime(){
echo "================配置时间同步====================="
\cp /var/spool/cron/root /var/spool/cron/root.$(date +%F) 2>/dev/null
NTPDATE=`grep ntpdate /var/spool/cron/root 2>/dev/null |wc -l`
if [ $NTPDATE -eq 0 ];then
/bin/rm -rf /etc/localtime && cp /usr/share/zoneinfo/Asia/Shanghai /etc/localtime && /usr/sbin/ntpdate ntp1.aliyun.com
echo "#times sync by lanny at $(date +%F)" >>/var/spool/cron/root
echo "*/5 * * * * /usr/sbin/ntpdate ntp1.aliyun.com >/dev/null 2>&1" >> /var/spool/cron/root
fi
echo '#crontab -l'
crontab -l
action "配置时间同步完成" /bin/true
echo "================================================="
echo ""
sleep 2
}
initHistory(){
echo "================配置history显示格式====================="
export HISTTIMEFORMAT="%F %T `whoami` "
echo 'export HISTTIMEFORMAT="%F %T `whoami` ' >> /etc/profile
echo '#grep HISTTIMEFORMAT /etc/profile '
grep HISTTIMEFORMAT /etc/profile
action "配置history显示格式" /bin/true
echo "================================================="
echo ""
sleep 2
}
initCADShutdown(){
echo "================关掉ctrl+alt+delete关机====================="
\cp /etc/init/control-alt-delete.conf /etc/init/control-alt-delete.conf.bak
sed -i 's#exec /sbin/shutdown -r now "Control-Alt-Deletepressed"#\#exec /sbin/shutdown -r now "Control-Alt-Deletepressed"#g' /etc/init/control-alt-delete.conf
action "关掉ctrl+alt+delete关机" /bin/true
echo "================================================="
echo ""
sleep 2
}
#add user and give sudoers
addUser(){
echo "===================新建用户======================"
#add user
while true
do
read -p "请输入新用户名:" name
NAME=`awk -F':' '{print $1}' /etc/passwd|grep -wx $name 2>/dev/null|wc -l`
if [ ${#name} -eq 0 ];then
echo "用户名不能为空,请重新输入。"
continue
elif [ $NAME -eq 1 ];then
echo "用户名已存在,请重新输入。"
continue
fi
useradd $name
break
done
#create password
while true
do
read -p "为 $name 创建一个密码:" pass1
if [ ${#pass1} -eq 0 ];then
echo "密码不能为空,请重新输入。"
continue
fi
read -p "请再次输入密码:" pass2
if [ "$pass1" != "$pass2" ];then
echo "两次密码输入不相同,请重新输入。"
continue
fi
echo "$pass2" |passwd --stdin $name
break
done
sleep 1
#add visudo
echo "#####add visudo#####"
\cp /etc/sudoers /etc/sudoers.$(date +%F)
SUDO=`grep -w "$name" /etc/sudoers |wc -l`
if [ $SUDO -eq 0 ];then
echo "$name ALL=(ALL) NOPASSWD: ALL" >>/etc/sudoers
echo '#tail -1 /etc/sudoers'
grep -w "$name" /etc/sudoers
sleep 1
fi
action "创建用户$name并将其加入visudo完成" /bin/true
echo "================================================="
echo ""
sleep 2
}
#Adjust the file descriptor(limits.conf)
initLimits(){
echo "===============加大文件描述符===================="
LIMIT=`grep nofile /etc/security/limits.conf |grep -v "^#"|wc -l`
if [ $LIMIT -eq 0 ];then
\cp /etc/security/limits.conf /etc/security/limits.conf.$(date +%F)
echo '* - nofile 65535'>>/etc/security/limits.conf
fi
echo '#tail -1 /etc/security/limits.conf'
tail -1 /etc/security/limits.conf
ulimit -HSn 65535
echo '#ulimit -n'
ulimit -n
action "配置文件描述符为65535" /bin/true
echo "================================================="
echo ""
sleep 2
}
#Optimizing the system kernel
initSysctl(){
echo "================优化内核参数====================="
SYSCTL=`grep "net.ipv4.tcp" /etc/sysctl.conf |wc -l`
if [ $SYSCTL -lt 10 ];then
\cp /etc/sysctl.conf /etc/sysctl.conf.$(date +%F)
cat >>/etc/sysctl.conf<<EOF
net.ipv4.tcp_fin_timeout = 2
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_keepalive_time = 600
net.ipv4.ip_local_port_range = 4000 65000
net.ipv4.tcp_max_syn_backlog = 16384
net.ipv4.tcp_max_tw_buckets = 36000
net.ipv4.route.gc_timeout = 100
net.ipv4.tcp_syn_retries = 1
net.ipv4.tcp_synack_retries = 1
net.core.somaxconn = 16384
net.core.netdev_max_backlog = 16384
net.ipv4.tcp_max_orphans = 16384
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
EOF
fi
\cp /etc/rc.local /etc/rc.local.$(date +%F)
modprobe nf_conntrack
echo "modprobe nf_conntrack">> /etc/rc.local
modprobe bridge
echo "modprobe bridge">> /etc/rc.local
sysctl -p
action "内核调优完成" /bin/true
echo "================================================="
echo ""
sleep 2
}
#menu2
menu2(){
while true
do
clear
cat << EOF
----------------------------------------
|****Please Enter Your Choice:[0-9]****|
----------------------------------------
(1) 新建一个用户并将其加入visudo
(2) 配置为国内YUM源镜像
(3) 配置中文字符集
(4) 禁用SELINUX及关闭防火墙
(5) 精简开机自启动
(6) 修改ssh默认端口及禁用root远程登录
(7) 设置时间同步
(8) 加大文件描述符
(9) 内核调优
(0) 返回上一级菜单
EOF
read -p "Please enter your Choice[0-9]: " input2
case "$input2" in
0)
clear
break
;;
1)
addUser
;;
2)
configYum
;;
3)
initI18n
;;
4)
initFirewall
;;
5)
initService
;;
6)
initSsh
;;
7)
syncSysTime
;;
8)
initLimits
;;
9)
initSysctl
;;
*) echo "----------------------------------"
echo "| Warning!!! |"
echo "| Please Enter Right Choice! |"
echo "----------------------------------"
for i in `seq -w 3 -1 1`
do
echo -ne "\b\b$i";
sleep 1;
done
clear
esac
done
}
#initTools
#menu
while true
do
clear
echo "========================================"
echo ' Linux Optimization '
echo "========================================"
cat << EOF
|-----------System Infomation-----------
| DATE :$DATE
| HOSTNAME :$HOSTNAME
| USER :$USER
| IP :$IPADDR
| DISK_USED :$DISK_SDA
| CPU_AVERAGE:$cpu_uptime
----------------------------------------
|****Please Enter Your Choice:[1-3]****|
----------------------------------------
(1) 一键优化
(2) 自定义优化
(3) 退出
EOF
#choice
read -p "Please enter your choice[0-3]: " input1
case "$input1" in
1)
addUser
configYum
initTools
initCADShutdown
initI18n
initFirewall
initService
initSsh
syncSysTime
initLimits
initSysctl
initVim
;;
2)
menu2
;;
3)
clear
break
;;
*)
echo "----------------------------------"
echo "| Warning!!! |"
echo "| Please Enter Right Choice! |"
echo "----------------------------------"
for i in `seq -w 3 -1 1`
do
echo -ne "\b\b$i";
sleep 1;
done
clear
esac
done
centos6系列系统安装完毕后,一键优化脚本.
细节:http://oldboy.blog.51cto.com/2561410/1336488
网络状态优化:http://oldboy.blog.51cto.com/2561410/1184228
定时任务优化:http://oldboy.blog.51cto.com/2561410/1216730
较简单: http://mofansheng.blog.51cto.com/8792265/1710247
较健全: http://chocolee.blog.51cto.com/8158455/1424587