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https://issues.apache.org/jira/browse/FLINK-11127?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16719004#comment-16719004
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Ufuk Celebi commented on FLINK-11127:
-------------------------------------
[~spoganshev] Yes, the port configuration is correct.
I'm aware of the {{StatefulSet}} workaround, but it is not feasible for larger
replica counts in my opinion, because it results in pods to be created
sequentially:
{quote}
For a StatefulSet with N replicas, when Pods are being deployed, they are
created sequentially, in order from \{0..N-1}.
[...]
When the nginx example above is created, three Pods will be deployed in the
order web-0, web-1, web-2. web-1 will not be deployed before web-0 is [Running
and Ready|https://kubernetes.io/docs/user-guide/pod-states/], and web-2 will
not be deployed until web-1 is Running and Ready.
{quote}
(https://kubernetes.io/docs/concepts/workloads/controllers/statefulset/#deployment-and-scaling-guarantees)
> 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: Distributed Coordination, Kubernetes, Metrics
> Affects Versions: 1.7.0
> Reporter: Ufuk Celebi
> Priority: Major
>
> 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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