***UNCHECKED*** Re: Best way to find the current alive jobmanager with HA mode zookeeper

[vino yang <ya...@gmail.com>]

Hi Yuan Youjun,

Actually, RestClusterClient has a method named getWebMonitorBaseUrl which
will retrieve the webmonitor's leader address when you submit job
automatically.[1]

Ideally, you do not need to retrieve JM by yourself. Currently, the
webmonitor is binding with JobManager, maybe if JM failover, you can not
find new web monitor?

Flink provided a component named "LeaderRetrievalService" to retrieval many
compoment's leader, based on Zookeeper, there is a implementation named
"ZooKeeperLeaderRetrievalService".

In ZooKeeperHaServices, it provided a method named
"getWebMonitorLeaderRetriever" to retrieve the web monitor's leader and
provided a method named "getJobManagerLeaderRetriever" to retrieve
JobManager's leader.  And ClusterClient#getJobManagerGateway used it.

[1]:
https://github.com/apache/flink/blob/master/flink-clients/src/main/java/org/apache/flink/client/program/rest/RestClusterClient.java#L755

Thanks, vino.


2018-07-25 11:37 GMT+08:00 Yuan,Youjun <yu...@baidu.com>:

> Hi all,
>
>
>
> I have a standalone cluster with 3 jobmanagers, and set *high-availability
> to zookeeper*. Our client submits job by REST API(POST /jars/:jarid/run),
> which means we need to know the host of the any of the current alive
> jobmanagers. The problem is that, how can we know which job manager is
> alive, or the host of current leader?  We don’t want to access a dead JM.
>
>
>
> Thanks.
>
> Youjun Yuan
>