Problems with CentOS

1.DNS problem, causing Yum to have no source

echo "NameServer 8.8.8.8" >>/etc/resolv.conf

2.CentOS 7 "ifconfig" command not found after minimal installation

1. IP addr
2. Yum Install net-tools

3. Configure network issues.

Setup method for automatic activation of eth0 under Linux at system startup
Method One,
1, NTSYSV
Determine if the network front tick?!

2, Vi/etc/sysconfig/network
OK: Networking=yes

3,/etc/sysconfig/network-scripts/ifcfg-eth0
Determine the above file:
Onboot=yes

Method Two,
# Vi/etc/sysconfig/network-scripts/ifcfg-eth0
All say there is onboot=yes this sentence can be activated automatically, but the configuration file is clearly there is still no effect, the boot always have to manually to activate.
Then, in the/etc/rc.d/rc.local file, add
Ifup eth0
Or
Ifconfig eth0 up
Eth0 is the network card to be activated.

Description
Method One, basically can solve the problem.
If the method is not after the configuration, then consider using method two, this method is more vigorous, please think twice.

Problems with CentOS