1.找出哪个包提供了ifconfig命令
yumprovidesifconfig
2.从输出样例中看出net-tools包提供了ifconfig命令，所以只安装net-tools包来使用ifconfig命令
Loadedplugins:fastestmirrorbase|3.6kB00:00:00extras|3.4kB00:00:00updates|3.4kB00:00:00(1/4):base/7/x86_64/group_gz|156kB00:00:00(2/4):extras/7/x86_64/primary_db|130kB00:00:00(3/4):base/7/x86_64/primary_db|5.7MB00:00:04(4/4):updates/7/x86_64/primary_db|3.6MB00:00:44Determiningfastestmirrors*base:mirrors.aliyun.com*extras:mirrors.cn99.com*updates:centosr4.centos.orgbase/7/x86_64/filelists_db|6.7MB00:00:04extras/7/x86_64/filelists_db|494kB00:00:00updates/7/x86_64/filelists_db|2.1MB00:00:03net-tools-2.0-0.22.20131004git.el7.x86_64:BasicnetworkingtoolsRepo:baseMatchedfrom:Filename:/sbin/ifconfig
3.安装net-tools包，安装完成后就可以使用ifconfig命令了
yuminstallnet-tools
