Vagrantのネットワークで躓いた ref: http://qiita.com/yoshiya64/items/62d85f645499bf5b7eb6

file0.txt

[root@localhost ~]# yum install dig
Geladene Plugins: fastestmirror
http://mirror.centos.org/centos/7/os/x86_64/repodata/repomd.xml: [Errno 14] curl#6 - "Could not resolve host: mirror.centos.org; Unbekannter Fehler"
Anderer Spiegelserver wird versucht.

file3.txt

[root@localhost ~]# service network restart
Restarting network (via systemctl):  [  OK  ]
[root@localhost ~]# 

file4.txt

[root@localhost yum.repos.d]# ping www.yahoo.co.jp
PING edge.g.yimg.jp (182.22.24.252) 56(84) bytes of data.
64 bytes from 182.22.24.252: icmp_seq=1 ttl=51 time=116 ms

ifcfg-ethX

NAME="enpXXX"
DEVICE="enpXXX"
ONBOOT=yes
NETBOOT=yes
UUID="XXX"
IPV6INIT=yes
BOOTPROTO=dhcp
TYPE=Ethernet
DNS1=8.8.8.8
DNS2=8.8.4.4