driver无法实现HA

driver的URL配置为jdbc:cobar://xx.xx.xx.3:8066,xx.xx.xx.4:8066/dbtest。
在xx.xx.xx.3 和xx.xx.xx.4这两台cobar server都运行正常时,可以正常实现负载均衡

关掉xx.xx.xx.3后,就无法获取到连接了,难道不应该是xx.xx.xx.3挂了,就直接连接xx.xx.xx.4吗?

Start by reproducing the JDBC URL scenario with both Cobar servers available, then stop xx.xx.xx.3 and observe how the driver obtains connections. Trace the driver’s handling of multiple Cobar endpoints and failover; done means connections continue through xx.xx.xx.4 when xx.xx.xx.3 is unavailable.

Written by the indexing model from the issue text.