CentOS 7.1 Bridge STPエラーメッセージ「Master connection not found or invalid」を有効にする

今日会社でLinux bridgeの構築をテストし、内部のdockerコンテナのネットワークを2層のカプセル化を経ずに外部に転送できるようにbridge機能を試してみたところ、「Bringing up interface eno 1677736:Error:Connection activation failed:Master connection not found or invalid」というエラーが発生しました.
具体的なエラーは次のとおりです.

Mar 16 10:56:04 cloud01 systemd[1]: Starting LSB: Bring up/down networking...
Mar 16 10:56:05 cloud01 network[876]: Bringing up loopback interface:  Could not load file '/etc/sysconfig/network-scripts/ifcfg-lo'
Mar 16 10:56:05 cloud01 network[876]: Could not load file '/etc/sysconfig/network-scripts/ifcfg-lo'
Mar 16 10:56:06 cloud01 network[876]: Could not load file '/etc/sysconfig/network-scripts/ifcfg-lo'
Mar 16 10:56:06 cloud01 network[876]: Could not load file '/etc/sysconfig/network-scripts/ifcfg-lo'
Mar 16 10:56:06 cloud01 network[876]: [  OK  ]
Mar 16 10:56:06 cloud01 network[876]: Bringing up interface eno16777736:  Error: Connection activation failed: Master connection not found or invalid
Mar 16 10:56:06 cloud01 network[876]: [FAILED]
Mar 16 10:56:06 cloud01 network[876]: Bringing up interface br0:  Could not load file '/etc/sysconfig/network-scripts/ifcfg-br0'
Mar 16 10:56:06 cloud01 network[876]: Could not load file '/etc/sysconfig/network-scripts/ifcfg-br0'
Mar 16 10:56:14 cloud01 network[876]: Determining IP information for br0... failed; no link present.  Check cable?
Mar 16 10:56:14 cloud01 network[876]: [FAILED]
Mar 16 10:56:14 cloud01 systemd[1]: network.service: control process exited, code=exited status=1
Mar 16 10:56:14 cloud01 systemd[1]: Failed to start LSB: Bring up/down networking.
Mar 16 10:56:14 cloud01 systemd[1]: Unit network.service entered failed state.

Googleを通じて、NetworkManagerを無効にしなければならないという答えが出ました.
次のコマンドを実行します.

systemctl stop NetworkManager
systemctl disable NetworkManager

再起動を選択するか、networkサービスを再起動するだけで修復できます.
 
有効化後の効果:

# brctl show
bridge name     bridge id               STP enabled     interfaces
br0             8000.000c295f4d67       yes             eno16777736

 
参考資料:
　　https://www.centos.org/forums/viewtopic.php?f=50&t=51000
本文はこれで終わります.ありがとうございます.