分享一个查看CentOS系统信息的脚本

最近在看《实战Linux Shell编程与服务器管理》，一边看一边练习，看到sed和awk时感觉这两个工具真是太好用了。学以致用，于是想平时想看看系统信息，总是去查命令，然后去一堆信息里去找，不如写个脚本来练练手，于是就有了InfoView4CentOS这个脚本。
代码托管在Github（也是来练习使用Github的），地址：https://github.com/callmepeanut/InfoView4CentOS
采用选单的方式，可以查看ip、硬件等信息，运行效果如下：

[root@localhost InfoView4CentOS]# ./InfoView4CentOS.sh
1) HostIp                 3) SystemVersion          5) NonDefault-LoginUsers
2) HardwareInfo           4) OpenPorts              6) Exit
Please input your choice:

1）查看IP

Please input your choice:1
===============NetworkInfo===============
Host ip is: 10.0.2.15
Please input your choice:

2）查看CPU、内存、硬盘空间、网卡等信息

Please input your choice:2
===============HardwareInfo===============
ProductName: VirtualBox
CPU:         Intel(R) Pentium(R) Dual  CPU  E2140  @ 1.60GHz
PhysicMem:   801408 kB
DiskSpace:   12G 25%used
NetWorkCard: PCnet/PCI II 79C970A
Please input your choice:

3）查看系统和内核版本

Please input your choice:3
===============SystemInfo===============
Release:         release 6.4 (Final)
Kernal Version:  2.6.32-358.el6.i686
System Bits:     32 Bit
Please input your choice:

4）查看端口开放情况

Please input your choice:4
===============OpenPortsInfo===============
OpenPorts:
127.0.0.1:9000    1430/php-fpm
0.0.0.0:3306     1656/mysqld
0.0.0.0:139       1771/smbd
0.0.0.0:111    1103/rpcbind
0.0.0.0:80      1423/nginx
0.0.0.0:22       1815/sshd
127.0.0.1:631      1292/cupsd
127.0.0.1:25     1753/master
0.0.0.0:445       1771/smbd
0.0.0.0:46943  1187/rpc.statd
127.0.0.1:199      1416/snmpd
:::139       1771/smbd
:::111    1103/rpcbind
:::22       1815/sshd
::1:631      1292/cupsd
:::60826  1187/rpc.statd
:::445       1771/smbd

5）查看非默认登录shell用户

Please input your choice:5
===============UsersInfo===============
peanut:x:500:500:peanut:/home/peanut:/bin/bash
mysql:x:27:27:MySQL Server:/var/lib/mysql:/bin/bash
seg:x:502:502::/home/seg:/bin/bash
Please input your choice:

6）退出

Please input your choice:6
Bye

输入错误

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Bad Choice
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