openstack虚机无法获取IP地址

compute2的虚机无法获取IP地址，compute3的虚机倒是可以，查看compute2虚机的启动日志，发现会有报错：

cloud-init[916]: 2020-03-19 07:49:10,403 - url_helper.py[WARNING]: Calling 'http://169.254.169.254/2009-04-04/meta-data/instance-id' failed [0/120s]: request error [HTTPConnectionPool(host='169.254.169.254', port=80): Max retries exceeded with url: /2009-04-04/meta-data/instance-id (Caused by NewConnectionError('<requests.packages.urllib3.connection.HTTPConnection object at 0x7f627b4aca58>: Failed to establish a new connection: [Errno 101] Network is unreachable',))]

查找发现169.254.169.254是controller节点的neutron-metadata-agent服务用来给计算节点发送元数据的ip。不通的话说明compute2节点和controller节点的数据平面网络有问题，检查发现是compute2节点的数据平面网线松动，导致数据平面不通。