当CentOS7进行最小化安装时，有很多工具包是没有的。
[root@vultr ~]# ifconfig
-bash: ifconfig: command not found
[root@vultr ~]# netstat
-bash: netstat: command not found
我们经常会使用到的命令，ifconfig、netstat等都没有。因为缺失了net-tools包。
[root@vultr ~]# yum install -y net-tools # 安装net-tools
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: mirror.wdc1.us.leaseweb.net
* epel: reflector.westga.edu
* extras: mirror.vcu.edu
* updates: ftpmirror.your.org
Resolving Dependencies
--> Running transaction check
---> Package net-tools.x86_64 0:2.0-0.24.20131004git.el7 will be installed
--> Finished Dependency Resolution Dependencies Resolved =============================================================================================================================================
Package Arch Version Repository Size
=============================================================================================================================================
Installing:
net-tools x86_64 2.0-0.24.20131004git.el7 base 306 k Transaction Summary
=============================================================================================================================================
Install 1 Package Total download size: 306 k
Installed size: 918 k
Downloading packages:
net-tools-2.0-0.24.20131004git.el7.x86_64.rpm | 306 kB 00:00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : net-tools-2.0-0.24.20131004git.el7.x86_64 1/1
Verifying : net-tools-2.0-0.24.20131004git.el7.x86_64 1/1 Installed:
net-tools.x86_64 0:2.0-0.24.20131004git.el7 Complete!
[root@vultr ~]# ifconfig | grep inet
inet 155.138.229.164 netmask 255.255.254.0 broadcast 155.138.229.255
inet6 fe80::5400:1ff:feff:86b7 prefixlen 64 scopeid 0x20<link>
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
[root@vultr ~]# netstat -lnp
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 2746/sshd
tcp6 0 0 :::22 :::* LISTEN 2746/sshd
udp 0 0 0.0.0.0:68 0.0.0.0:* 3381/dhclient
udp 0 0 127.0.0.1:323 0.0.0.0:* 1573/chronyd
udp6 0 0 ::1:323 :::* 1573/chronyd
Active UNIX domain sockets (only servers)
Proto RefCnt Flags Type State I-Node PID/Program name Path
unix 2 [ ACC ] STREAM LISTENING 12953 1/systemd /run/systemd/private
unix 2 [ ACC ] STREAM LISTENING 14775 1/systemd /run/dbus/system_bus_socket
unix 2 [ ACC ] STREAM LISTENING 7397 1/systemd /run/systemd/journal/stdout
unix 2 [ ACC ] SEQPACKET LISTENING 13039 1/systemd /run/udev/control
安装net-tools工具包之后，ifconfig|netstat等网络相关的命令便能使用了。