Day31 课堂作业

1. 集群简单介绍

1、什么是集群？

简单地说，集群就是一堆机器做同一件事，
例如：www.jd.com提供卖东西服务这就是一件事，可能是几千台服务器，在背后运转支撑这个网站。
www.baidu.com看着就是一个搜索框，背后可能是上万台服务器。

2、为什么企业要用集群？

• a. 7*24服务，需要多台机器同时工作，互为实时备份。
• b. 高并发访问，需要多台服务器同时提供服务。

3、集群特点

• a.数据量大、用户多
• b.7*24持续服务
• c.高并发
• d.用户分布广泛，网络情况复杂

4、形象描述集群

中小企业集群架构示意图

2. 架构集群前的规划

表1：服务器架构功能规划表

表2：主机IP规划表

表3：服务器目录结构规划表

3. 架构集群前的准备

本模板机选择的操作系统为Linux，版本为CentOS Linux release 7.6.1810，内核为：3.10.0-957.el7.x86_64

3.1、模板机操作：

1、添加一块网卡

1)、点击 编辑虚拟机设置

2)、点击 添加

3)、选择网络适配器，选完后点击 下一步

4)、选择NAT模式，选完后点击 完成

5)、选择网络适配器2，选完后右边选择 LAN区段 然后，再点击 LAN区段

6)、选择 添加

7)、设置LAN区段的IP段，选完后点击 确定

8)、点击下拉按钮，然后后选择 刚配置的LAN区段 然后，再点击 确定

2、图形化配置网卡

1)、点击 开启此虚拟机

2)、在命令行输入 nmtui命令，进行图形化配置网卡

[root@oldboyedu ~]# nmtui

3)、选择第一个（默认），然后回车

4)、点击 add

5)、选择第二个：以太网

6)、依照下面步骤配置 eth1

7)、依照下面步骤配置 eth0

8)、点击 Back

9)、上下键选择Quit

10)、重启网卡，命令如下

systemctl restart network

10)、检查IP是否配置正确

--------------------------------------------------------------
==>输入ip a命令<==
--------------------------------------------------------------
[root@oldboyedu ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
       
--------------------------------------------------------------
==>eth0网卡信息<==
--------------------------------------------------------------
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:92:46:6a brd ff:ff:ff:ff:ff:ff
    inet 10.0.0.222/24 brd 10.0.0.255 scope global noprefixroute eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::39be:515d:75e2:7e4a/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
       
 --------------------------------------------------------------
==>eth1网卡信息<==
--------------------------------------------------------------
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:92:46:74 brd ff:ff:ff:ff:ff:ff
    inet 172.16.1.200/24 brd 172.16.1.255 scope global noprefixroute eth1
       valid_lft forever preferred_lft forever
    inet6 fe80::7:b893:a3f9:910d/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever

4. 网站集群架构系统优化

先优化模板机，然后克隆优化后的模板机，有的优化是生产场景优化，为了实验的方便，可以省略

注：标有（实验环境）的，是实验环境，生产环境还是有变化的；标有（生产环境）是生产场景的优化，此处省略

4.1、模板机操作：（实验环境）

1、规范目录

--------------------------------------------------------------
==>命令如下<==
--------------------------------------------------------------
mkdir -p /server/tools
mkdir -p /server/scripts

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# mkdir -p /server/tools
[root@oldboyedu ~]# mkdir -p /server/scripts

2、配置所有主机域名解析

--------------------------------------------------------------
==>命令如下<==
--------------------------------------------------------------
cat >/etc/hosts<<EOF
127.0.0.1    localhost localhost.localdomain localhost4 localhost4.localdomain4
::1          localhost localhost.localdomain localhost6 localhost6.localdomain6
172.16.1.5 lb01
172.16.1.6 lb02
172.16.1.7 web01
172.16.1.8 web02
172.16.1.9 web03
172.16.1.31 nfs01
172.16.1.41 backup
172.16.1.51 db01 db01.etiantian.org
172.16.1.61 m01
EOF

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# cat >/etc/hosts<<EOF
> 127.0.0.1    localhost localhost.localdomain localhost4 localhost4.localdomain4
> ::1          localhost localhost.localdomain localhost6 localhost6.localdomain6
> 172.16.1.5 lb01
> 172.16.1.6 lb02
> 172.16.1.7 web01
> 172.16.1.8 web02
> 172.16.1.9 web03
> 172.16.1.31 nfs01
> 172.16.1.41 backup
> 172.16.1.51 db01 db01.etiantian.org
> 172.16.1.61 m01
> EOF

3、基础优化操作项：更新yum源信息

第一个：就近使用yum源地址，安装软件更快。

curl -s -o /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo

第二个：安装RHEL/CentOS官方源不提供的软件包

curl -s -o /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# curl -s -o /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
[root@oldboyedu ~]# curl -s -o /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo

4、安全优化

1、关闭 selinux

--------------------------------------------------------------
==>命令如下<==
--------------------------------------------------------------
sed -i 's#SELINUX=.*#SELINUX=disabled#g' /etc/selinux/config
sed -i 's/SELINUX=enforcing/SELINUX=disabled/' /etc/selinux/config
grep SELINUX=disabled /etc/selinux/config 
setenforce 0
getenforce

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# sed -i 's#SELINUX=.*#SELINUX=disabled#g' /etc/selinux/config
[root@oldboyedu ~]# sed -i 's/SELINUX=enforcing/SELINUX=disabled/' /etc/selinux/config
[root@oldboyedu ~]# grep SELINUX=disabled /etc/selinux/config 
# SELINUX=disabled
SELINUX=disabled
[root@oldboyedu ~]# setenforce 0
[root@oldboyedu ~]# getenforce
Permissive

2、关闭firewalld防火墙服务 （实验环境）

--------------------------------------------------------------
==>命令如下<==
--------------------------------------------------------------
systemctl stop firewalld
systemctl disable firewalld
systemctl status firewalld

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# systemctl stop firewalld
[root@oldboyedu ~]# systemctl disable firewalld
Removed symlink /etc/systemd/system/multi-user.target.wants/firewalld.service.
Removed symlink /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.
[root@oldboyedu ~]# systemctl status firewalld
● firewalld.service - firewalld - dynamic firewall daemon
   Loaded: loaded (/usr/lib/systemd/system/firewalld.service; disabled; vendor preset: enabled)
   Active: inactive (dead)
     Docs: man:firewalld(1)

Apr 12 21:48:12 oldboyedu systemd[1]: Starting firewalld - dynamic firewall daemon...
Apr 12 21:48:14 oldboyedu systemd[1]: Started firewalld - dynamic firewall daemon.
Apr 12 22:18:32 oldboyedu systemd[1]: Stopping firewalld - dynamic firewall daemon...
Apr 12 22:18:32 oldboyedu systemd[1]: Stopped firewalld - dynamic firewall daemon.
[root@oldboyedu ~]# 

5、基础优化操作项：设置普通用户提权操作（可选优化）

提权oldboy可以利用sudo

--------------------------------------------------------------
==>命令如下<==
--------------------------------------------------------------
useradd oldboy
echo 123456|passwd --stdin oldboy
\cp /etc/sudoers /etc/sudoers.ori
echo "oldboy  ALL=(ALL) NOPASSWD: ALL " >>/etc/sudoers
tail -1 /etc/sudoers
visudo -c

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# useradd oldboy
[root@oldboyedu ~]# echo 123456|passwd --stdin oldboy
Changing password for user oldboy.
passwd: all authentication tokens updated successfully.
[root@oldboyedu ~]# \cp /etc/sudoers /etc/sudoers.ori
[root@oldboyedu ~]# echo "oldboy ALL=(ALL) NOPASSWD: ALL " >>/etc/sudoers
[root@oldboyedu ~]# tail -1 /etc/sudoers
oldboy ALL=(ALL) NOPASSWD: ALL 
[root@oldboyedu ~]# visudo -c
/etc/sudoers: parsed OK

6、设置系统中文UTF8字符集

[root@oldboyedu ~]# cat /etc/locale.conf
LANG="en_US.UTF-8"

--------------------------------------------------------------
==>命令如下<==
--------------------------------------------------------------
cp /etc/locale.conf  /etc/locale.conf.ori
echo 'LANG="zh_CN.UTF-8"' >/etc/locale.conf  
source /etc/locale.conf 
echo $LANG
或者
cp /etc/locale.conf  /etc/locale.conf.ori
localectl set-locale LANG="zh_CN.UTF-8"
cat /etc/locale.conf 

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# cp /etc/locale.conf  /etc/locale.conf.ori
[root@oldboyedu ~]# echo 'LANG="zh_CN.UTF-8"' >/etc/locale.conf  
[root@oldboyedu ~]# source /etc/locale.conf 
[root@oldboyedu ~]# echo $LANG
zh_CN.UTF-8

7、基础优化操作项：时间同步设置

设置系统时间同步

--------------------------------------------------------------
==>命令如下<==
--------------------------------------------------------------
yum install ntpdate -y
/usr/sbin/ntpdate ntp3.aliyun.com
echo '#crond-id-001:time sync by oldboy' >>/var/spool/cron/root
echo "*/5 * * * * /usr/sbin/ntpdate ntp3.aliyun.com >/dev/null 2>&1">>/var/spool/cron/root
crontab -l

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# yum install ntpdate -y
[root@oldboyedu ~]# /usr/sbin/ntpdate ntp3.aliyun.com
12 Apr 14:27:37 ntpdate[8480]: step time server 203.107.6.88 offset -28784.935648 sec
[root@oldboyedu ~]# echo '#crond-id-001:time sync by oldboy' >>/var/spool/cron/root
[root@oldboyedu ~]# echo "*/5 * * * * /usr/sbin/ntpdate ntp3.aliyun.com >/dev/null 2>&1">>/var/spool/cron/root
[root@oldboyedu ~]# crontab -l
#crond-id-001:time sync by oldboy
*/5 * * * * /usr/sbin/ntpdate ntp3.aliyun.com >/dev/null 2>&1

8、基础优化操作项：提升命令行操作安全性（可选优化）

提升命令行安全（可选配置）

--------------------------------------------------------------
==>命令如下<==
--------------------------------------------------------------
echo 'export TMOUT=300' >>/etc/profile
echo 'export HISTSIZE=5' >>/etc/profile
echo 'export HISTFILESIZE=5' >>/etc/profile
tail -3 /etc/profile
. /etc/profile

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# echo 'export TMOUT=300' >>/etc/profile
[root@oldboyedu ~]# echo 'export HISTSIZE=5' >>/etc/profile
[root@oldboyedu ~]# echo 'export HISTFILESIZE=5' >>/etc/profile
[root@oldboyedu ~]# tail -3 /etc/profile
export TMOUT=300
export HISTSIZE=5
export HISTFILESIZE=5
[root@oldboyedu ~]# . /etc/profile

9、基础优化操作项：加大文件描述符

加大文件描述

--------------------------------------------------------------
==>命令如下<==
--------------------------------------------------------------
echo '*               -       nofile          65535 ' >>/etc/security/limits.conf 
tail -1 /etc/security/limits.conf
ulimit -SHn   65535 
ulimit -n       

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# echo '*               -       nofile          65535 ' >>/etc/security/limits.conf 
[root@oldboyedu ~]# tail -1 /etc/security/limits.conf
*               -       nofile          65535 
[root@oldboyedu ~]# ulimit -SHn   65535 
[root@oldboyedu ~]# ulimit -n
65535

10、基础优化操作项：优化系统内核

--------------------------------------------------------------
==>命令如下<==
--------------------------------------------------------------
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
#以下参数是对iptables防火墙的优化，防火墙不开会提示，可以忽略不理。
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
net.core.wmem_default = 8388608
net.core.rmem_default = 8388608
net.core.wmem_max = 16777216
net.core.rmem_max = 16777216
EOF
sysctl -p

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# 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
> #以下参数是对iptables防火墙的优化，防火墙不开会提示，可以忽略不理。
> 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
> net.core.wmem_default = 8388608
> net.core.rmem_default = 8388608
> net.core.wmem_max = 16777216
> net.core.rmem_max = 16777216
> EOF
[root@oldboyedu ~]# sysctl -p
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
sysctl: cannot stat /proc/sys/net/nf_conntrack_max: 没有那个文件或目录
sysctl: cannot stat /proc/sys/net/netfilter/nf_conntrack_max: 没有那个文件或目录
sysctl: cannot stat /proc/sys/net/netfilter/nf_conntrack_tcp_timeout_established: 没有那个文件或目录
sysctl: cannot stat /proc/sys/net/netfilter/nf_conntrack_tcp_timeout_time_wait: 没有那个文件或目录
sysctl: cannot stat /proc/sys/net/netfilter/nf_conntrack_tcp_timeout_close_wait: 没有那个文件或目录
sysctl: cannot stat /proc/sys/net/netfilter/nf_conntrack_tcp_timeout_fin_wait: 没有那个文件或目录
net.core.wmem_default = 8388608
net.core.rmem_default = 8388608
net.core.wmem_max = 16777216
net.core.rmem_max = 16777216
[root@oldboyedu ~]# sysctl -p

11、基础优化操作项：安装系统常用软件

CentOS6和CentOS7都要安装的企业运维常用基础工具包

yum install tree nmap dos2unix lrzsz nc lsof wget tcpdump htop iftop iotop sysstat nethogs -y

CentOS7要安装的企业运维常用基础工具包

yum install psmisc net-tools bash-completion vim-enhanced -y

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# yum install tree nmap dos2unix lrzsz nc lsof wget tcpdump htop iftop iotop sysstat nethogs -y
[root@oldboyedu ~]# yum install psmisc net-tools bash-completion vim-enhanced -y

12、扩展优化操作项-修改yum.conf文件配置信息

保留yum安装的软件包
将/etc/yum.conf中的keepcache=0改为keepcache=1，为日后一键安装网站集群留好rpm及依赖工具包。

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# vim /etc/yum.conf 
[root@oldboyedu ~]# grep "keepcache" /etc/yum.conf
keepcache=1
[root@oldboyedu ~]# 

13. 锁定关键系统文件（生产环境）

比如：/etc/passwd、/etc/shadow、/etc/group、/etc/gshadow、/etc/inittab，
处理以上内容后把chattr、lsattr改名为oldboy，转移走，这样就安全多了。

14、基础优化操作项：优化SSH远程连接效率（生产环境）

禁止root远程连接
修改默认22端口，改为52113
监听内网服务器IP

15、清空/etc/issue、/etc/issue.net，去除系统及内核版本登录前的屏幕显示

--------------------------------------------------------------
==>命令如下<==
--------------------------------------------------------------
>/etc/issue
>/etc/issue.net

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# >/etc/issue
[root@oldboyedu ~]# >/etc/issue.net

16、清除多余的系统虚拟用户账号（生产环境）

17、 为grub引导菜单加密码（生产环境）

18. 禁止主机被ping（内核参数）（生产环境）

19. 打补丁并升级有已知漏洞的软件（生产环境）

yum update

20、精简开机自启动服务

--------------------------------------------------------------
==>命令如下<==
--------------------------------------------------------------
systemctl list-unit-files |grep enable|egrep -v "sshd.service|crond.service|sysstat|rsyslog|^NetworkManager.service|irqbalance.service"|awk '{print "systemctl disable",$1}'|bash
systemctl list-unit-files |grep enable

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@oldboyedu ~]# systemctl list-unit-files |grep enable|egrep -v "sshd.service|crond.service|sysstat|rsyslog|^NetworkManager.service|irqbalance.service"|awk '{print "systemctl disable",$1}'|bash
Removed symlink /etc/systemd/system/multi-user.target.wants/abrt-ccpp.service.
Removed symlink /etc/systemd/system/multi-user.target.wants/abrt-oops.service.
Removed symlink /etc/systemd/system/multi-user.target.wants/abrt-vmcore.service.
Removed symlink /etc/systemd/system/multi-user.target.wants/abrt-xorg.service.
Removed symlink /etc/systemd/system/multi-user.target.wants/abrtd.service.
Removed symlink /etc/systemd/system/multi-user.target.wants/auditd.service.
Failed to execute operation: Unit name autovt@.service is missing the instance name.
Removed symlink /etc/systemd/system/multi-user.target.wants/NetworkManager.service.
Removed symlink /etc/systemd/system/dbus-org.freedesktop.NetworkManager.service.
Removed symlink /etc/systemd/system/dbus-org.freedesktop.nm-dispatcher.service.
Removed symlink /etc/systemd/system/network-online.target.wants/NetworkManager-wait-online.service.
Failed to execute operation: No such file or directory
Failed to execute operation: Unit name getty@.service is missing the instance name.
Removed symlink /etc/systemd/system/basic.target.wants/microcode.service.
Removed symlink /etc/systemd/system/multi-user.target.wants/postfix.service.
Removed symlink /etc/systemd/system/sysinit.target.wants/rhel-autorelabel.service.
Removed symlink /etc/systemd/system/multi-user.target.wants/rhel-configure.service.
Removed symlink /etc/systemd/system/basic.target.wants/rhel-dmesg.service.
Removed symlink /etc/systemd/system/sysinit.target.wants/rhel-domainname.service.
Removed symlink /etc/systemd/system/sysinit.target.wants/rhel-import-state.service.
Removed symlink /etc/systemd/system/sysinit.target.wants/rhel-loadmodules.service.
Removed symlink /etc/systemd/system/local-fs.target.wants/rhel-readonly.service.
Removed symlink /etc/systemd/system/default.target.wants/systemd-readahead-collect.service.
Removed symlink /etc/systemd/system/system-update.target.wants/systemd-readahead-drop.service.
Removed symlink /etc/systemd/system/default.target.wants/systemd-readahead-replay.service.
Removed symlink /etc/systemd/system/multi-user.target.wants/tuned.service.
Removed symlink /etc/systemd/system/vmtoolsd.service.requires/vgauthd.service.
Removed symlink /etc/systemd/system/multi-user.target.wants/vmtoolsd.service.
Removed symlink /etc/systemd/system/default.target.
Removed symlink /etc/systemd/system/multi-user.target.wants/remote-fs.target.
[root@oldboyedu ~]# systemctl list-unit-files |grep enable
autovt@.service                               enabled 
crond.service                                 enabled 
getty@.service                                enabled 
irqbalance.service                            enabled 
rsyslog.service                               enabled 
sshd.service                                  enabled 
[root@oldboyedu ~]# 

保留的服务：
sshd、crond、sysstat、rsyslog、NetworkManager、irqbalance

企业生产最小化原则：
1、安装软件包最小化。
2、用户权限最小化。
3、目录文件权限最小化。
4、自启动服务最小化。
5、服务运行用户最小化。

[root@oldboyedu ~]# netstat -lntup
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name    
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      7072/sshd           
tcp6       0      0 :::22                   :::*                    LISTEN      7072/sshd 

21、显示优化（可选优化）

1, vim /etc/bashrc-------用vim编辑/etc/bashrc文件

[root@oldboy-58-wjc ~]# vim /etc/bashrc

2，: set nu ---------显示行号

3，按小键盘向下箭头按键，找到第41行

4，把光标移动到“[”左边，按i进入编辑模式，按#键

5，按ESC键，退出编辑模式，然后按“o（哦）”，到下一行进入编辑模式。

6，粘贴 :

[ "$PS1" = "\\s-\\v\\\$ " ] && PS1="[\[\e[34;1m\]\u@\[\e[0m\]\[\e[32;1m\]\H\[\e[0m\] \[\e[31;1m\]\w\[\e[0m\]]\\$ "

（粘贴的东西，以[开头，以”结尾，就是全部，万万别粘贴错了）

7，按esc退出编辑模式，而后按 : wq，保存退出

8，输入‘su’

如下图所示

4.2、模板机拍摄快照

4.3、先克隆三台（以模板机为样机，进行克隆）

表1：三台克隆机配置的规划如下

注意：克隆之前，模板机要关机：

1)、选择 模板机，点击 管理，然后选择 克隆

2)、点击 下一步

3)、选择 现有快照，然后选择 优化后的模板，选择完毕后点击下一步

4)、选择创建连接克隆（比较节省资源），选择完毕后点击下一步

5)、设置虚拟机名称，点击 浏览，选择事前规划好的 位置（不要乱放，事先规划好）

6)、点击 关闭，这样第一台克隆机就完成了，剩下的两台重复以上步骤

7)、最终结果如下：

4.4、配置克隆机

克隆机的配置：
1：修改配置网卡（eth0、eth1）
2：修改主机名

--------------------------------------------------------------
==>命令如下<==
--------------------------------------------------------------
vim /etc/sysconfig/network-scripts/ifcfg-eth0
vim /etc/sysconfig/network-scripts/ifcfg-eth1
hostnamectl set-hostname web01
su
systemctl restart network

--------------------------------------------------------------
==>演示如下<==
--------------------------------------------------------------
[root@web01 ~]# vim /etc/sysconfig/network-scripts/ifcfg-eth0
[root@web01 ~]# vim /etc/sysconfig/network-scripts/ifcfg-eth1
[root@web01 ~]# hostnamectl set-hostname web01
[root@oldboyedu ~]# su
[root@web01 ~]# systemctl restart network

注意：如果在远程连接工具如xshell上操作后，修改之后xshell会连不上，需修改连接的配置信息

最终结果如下：