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kranthij29_188881 avatar image
kranthij29_188881 asked ·

Reinstalling DSE via OpsCenter, getting "Unable to connect via JMX"

Hello Team,

getting below error after giving all the node and parameters and trying to install.

we did a cleanup already existing DSE cassandra and tryin to install a fresh one.

Please suggest any idea on below error on where to check.

Thanks in Advance.

ERROR [async-dispatch-5] 2020-05-22 06:10:36,832Z Can't connect to Cassandra (All host(s) tried for query failed (tried: /127.0.0.1:9042 (com.datastax.driver.core.exceptions.TransportException: [/127.0.0.1:9042] Cannot connect))), retrying soon.
INFO [async-dispatch-5] 2020-05-22 06:10:36,833Z Starting JMXComponent
ERROR [async-dispatch-5] 2020-05-22 06:10:36,834Z Unable to connect via JMX, target cassandra is likely unavailable or unreachable, please check cassandra health and connection settings jmx_host: 127.0.0.1 jmx_port: 7199 jmx credentials withheld from logging.
INFO [async-dispatch-5] 2020-05-22 06:10:36,835Z Starting JMXComponent
ERROR [async-dispatch-5] 2020-05-22 06:10:36,836Z Unable to connect via JMX, target cassandra is likely unavailable or unreachable, please check cassandra health and connection settings jmx_host: 127.0.0.1 jmx_port: 7199 jmx credentials withheld from logging.
INFO [async-dispatch-5] 2020-05-22 06:10:36,837Z Starting JMXComponent
ERROR [async-dispatch-5] 2020-05-22 06:10:36,837Z Unable to connect via JMX, target cassandra is likely unavailable or unreachable, please check cassandra health and connection settings jmx_host: 127.0.0.1 jmx_port: 7199 jmx credentials withheld from logging.
INFO [async-dispatch-5] 2020-05-22 06:10:36,838Z Starting JMXComponent
ERROR [async-dispatch-5] 2020-05-22 06:10:36,839Z Unable to connect via JMX, target cassandra is likely unavailable or unreachable, please check cassandra health and connection settings jmx_host: 127.0.0.1 jmx_port: 7199 jmx credentials withheld from logging.
INFO [async-dispatch-5] 2020-05-22 06:10:36,840Z Starting StompComponent
INFO [async-dispatch-5] 2020-05-22 06:10:36,841Z SSL communication is disabled
INFO [async-dispatch-5] 2020-05-22 06:10:36,841Z Creating stomp connection to 10.41.48.74:61620
WARN [async-dispatch-5] 2020-05-22 06:10:41,844Z Attempted to ping opscenterd on stomp but did not receive a reply in time, will retry again later.
INFO [async-dispatch-5] 2020-05-22 06:10:41,845Z Starting JMXComponent
ERROR [async-dispatch-5] 2020-05-22 06:10:41,846Z Unable to connect via JMX, target cassandra is likely unavailable or unreachable, please check cassandra health and connection settings jmx_host: 127.0.0.1 jmx_port: 7199 jmx credentials withheld from logging.
INFO [async-dispatch-5] 2020-05-22 06:10:41,847Z Finished starting system.
INFO [async-dispatch-8] 2020-05-22 06:10:51,848Z Starting system.
INFO [async-dispatch-8] 2020-05-22 06:10:51,850Z Configuration change for component class opsagent.nodedetails.distributed_repair.DistributedRepairComponent: before:
{:notification-jmx-pool JMXComponent #{:jmx-host 127.0.0.1, :jmx-user cassandra, :jmx-pass *REDACTED*, :jmx-port 7199, :capacity 1, :jmx-queue-poll-timeout 10, :trigger
-jmx-down opsagent.util$debounce_last$fn__1317@65fa5d10, :wrapper-fn , :shutdown-fn , :error Failed to retrieve RMIServer stub: javax.naming.ServiceUnavailableException
[Root exception is java.rmi.ConnectException: Connection refused to host: 127.0.0.1; nested exception is:
java.net.ConnectException: Connection refused (Connection refused)]}}, after: {:notification-jmx-pool nil}
INFO [async-dispatch-8] 2020-05-22 06:10:51,851Z The following components have had a config change and will be rebuilt and restarted: (:distributed-repair-component)
INFO [async-dispatch-8] 2020-05-22 06:10:51,851Z The component restart for (:distributed-repair-component) when accounting for dependencies requires these component
s to be restarted #{:http-server :distributed-repair-component}
INFO [async-dispatch-8] 2020-05-22 06:10:51,853Z Starting JMXComponent


opscenterinstallation
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1 Answer

Erick Ramirez avatar image
Erick Ramirez answered ·

@kranthij29_188881 It looks like you haven't given the correct parameters to OpsCenter and it is trying to connect to the node on localhost (127.0.0.1). This won't work unless both OpsCenter and DSE are running on the same server.

We will need lots more information about your cluster in order to troubleshoot your issue but it will be challenging doing it in a Q&A format so I suggest you log a DataStax Support ticket (requires a current subscription account) so one of our engineers can assist you. Cheers!

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Hi Thanks for the update, we have gone through some other way to install it using PAckages.

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Not a problem. Cheers!

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