FAQ-Zookeeper 启动失败 Port already in use: 0

问题描述/异常栈
zookeeper server 启动失败，.out 日志打印以下报错 
Error: Exception thrown by the agent : java.rmi.server.ExportException: Port already in use: 0; nested exception is: 
        java.net.BindException: Address already in use (Bind failed)
发现版本
解决方案
重启 NetworkManager
systemctl restart NetworkManager
问题原因
NetworkManager 未知问题

作者：lilingwei01