cobar cluster 配置没生效

cobar cluster 配置没有生效，cobar日志未提示错误。请问cobar cluster之间是通过什么协议做心跳的？配置如下；


192.160.28.44
1


192.160.28.45
2


执行结果：
mysql> show cobar_cluster;
Empty set (0.01 sec)

Start by reproducing the shown cluster configuration and running `show cobar_cluster`, then determine how Cobar discovers cluster nodes and performs heartbeat communication. Done means explaining why the result is empty and identifying the configuration or behavior that must change.

Written by the indexing model from the issue text.