Error: Connection activation failed: Device not managed by NetworkManager 解决

Open SSH With root permissions and try this!

1. Remove Network Manager from startup Services.
chkconfig NetworkManager off

2. Add Default Net Manager
chkconfig network on

Stop NetworkManager first
service NetworkManager stop

and then start Default Manager
service network start

 3.chkconfig --list

check it out the NetworkManger,and open it with the command chkconfig NetworkManager on

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or you can change it easy:system-config-network
uncheck the box that sets the eth0 as managed by NetworkManager and set IP info from there.

system-config-services
stop and disable NetworkManager , start and enable network

you have problem because both of NetworkManager and Network using same Network driver and default network blocking access for NetworkManager. if you disable NetworkManager your problem will disappeared after restart.

vmware 7 install CentOS 6 notes:

bring up the network of the ethnet,it should modify the network-scripts/ifcfg-ethx,add the paramenter below

onboot = yes

BOORPROTO=dhcp

it is necessary!