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https://issues.apache.org/jira/browse/FLINK-11127?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16962337#comment-16962337
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Ken commented on FLINK-11127:
-----------------------------

[~hwanju], I upgraded from 1.7 to 1.8. Previously I use the workaround fix. 
With 1.8, I noticed that 
{code:java}
Association with remote system 
[akka.tcp://flink-metrics@<JOB_MANAGER_HOSTNAME>:<PORT> has failed
{code}
has surface again. This does not happen when I start the JM and TMs at the 
beginning. I was able to force this error by simply "cancel" the job and let it 
auto-restart. I tried both the workaround as well as removing 
{code:java}
taskmanager.host{code}
and use
{code:java}
taskmanager.network.bind-policy: ip{code}
Whenever I "cancel" the job through the UI, the warning shows up in JM and TMs, 
and the statistics and metrics in the UI stopped working.  

> Make metrics query service establish connection to JobManager
> -------------------------------------------------------------
>
>                 Key: FLINK-11127
>                 URL: https://issues.apache.org/jira/browse/FLINK-11127
>             Project: Flink
>          Issue Type: Improvement
>          Components: Deployment / Kubernetes, Runtime / Coordination, Runtime 
> / Metrics
>    Affects Versions: 1.7.0
>            Reporter: Ufuk Celebi
>            Priority: Major
>              Labels: pull-request-available
>          Time Spent: 10m
>  Remaining Estimate: 0h
>
> As part of FLINK-10247, the internal metrics query service has been separated 
> into its own actor system. Before this change, the JobManager (JM) queried 
> TaskManager (TM) metrics via the TM actor. Now, the JM needs to establish a 
> separate connection to the TM metrics query service actor.
> In the context of Kubernetes, this is problematic as the JM will typically 
> *not* be able to resolve the TMs by name, resulting in warnings as follows:
> {code}
> 2018-12-11 08:32:33,962 WARN  akka.remote.ReliableDeliverySupervisor          
>               - Association with remote system 
> [akka.tcp://flink-metrics@flink-task-manager-64b868487c-x9l4b:39183] has 
> failed, address is now gated for [50] ms. Reason: [Association failed with 
> [akka.tcp://flink-metrics@flink-task-manager-64b868487c-x9l4b:39183]] Caused 
> by: [flink-task-manager-64b868487c-x9l4b: Name does not resolve]
> {code}
> In order to expose the TMs by name in Kubernetes, users require a service 
> *for each* TM instance which is not practical.
> This currently results in the web UI not being to display some basic metrics 
> about number of sent records. You can reproduce this by following the READMEs 
> in {{flink-container/kubernetes}}.
> This worked before, because the JM is typically exposed via a service with a 
> known name and the TMs establish the connection to it which the metrics query 
> service piggybacked on.
> A potential solution to this might be to let the query service connect to the 
> JM similar to how the TMs register.
> I tagged this ticket as an improvement, but in the context of Kubernetes I 
> would consider this to be a bug.



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