I follow this doc to setup mesos cluster. There are three vm(ubuntu 12, centos 6.5, centos 7.2). config in each mathine: After start zookeeper, mesos-master and mesos-slave in three vm, I can view the mesos webui(10.142.55.190:5050), but agents count is 0. After a little time, mesos page get error: Failed to connect to 10.142.55.190:5050! Retrying in 16 seconds… (Now I