ambari throwing error with RM

[#1]

Team,

When I checked ambari logs then I see following error, any idea why we have this error message ?

01 Mar 2017 05:40:06,209 ERROR [ambari-metrics-retrieval-service-thread-1] MetricsRetrievalService:421 - Unable to retrieve metrics from http://m2.hdp22:8744/api/v1/topology/summary?field=topologies. Subsequent failures will be suppressed from the log for 20 minutes.

java.net.ConnectException: Connection refused

at java.net.PlainSocketImpl.socketConnect(Native Method)

at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339)

at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200)

at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182)

at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)

at java.net.Socket.connect(Socket.java:579)

at sun.net.NetworkClient.doConnect(NetworkClient.java:175)

at sun.net.www.http.HttpClient.openServer(HttpClient.java:432)

at sun.net.www.http.HttpClient.openServer(HttpClient.java:527)

at sun.net.www.http.HttpClient.<init>(HttpClient.java:211)

at sun.net.www.http.HttpClient.New(HttpClient.java:308)

at sun.net.www.http.HttpClient.New(HttpClient.java:326)

at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:996)

at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:932)

at sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:850)

at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1300)

at java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:468)

at org.apache.ambari.server.controller.internal.URLStreamProvider.processURL(URLStreamProvider.java:218)

at org.apache.ambari.server.controller.internal.URLStreamProvider.processURL(URLStreamProvider.java:142)

at org.apache.ambari.server.controller.internal.URLStreamProvider.readFrom(URLStreamProvider.java:116)

at org.apache.ambari.server.controller.internal.URLStreamProvider.readFrom(URLStreamProvider.java:121)

at org.apache.ambari.server.state.services.MetricsRetrievalService$MetricRunnable.run(MetricsRetrievalService.java:382)

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)

at java.lang.Thread.run(Thread.java:745)

01 Mar 2017 05:46:02,006 WARN [ambari-client-thread-138] Errors:173 - The following warnings have been detected with resource and/or provider classes

[#2]

@Saurabh

Which version of ambari is it ? (NOTE: for very older version of ambari there were few known issues like "BUG-33557"

https://docs.hortonworks.com/HDPDocuments/Ambari-2.1.0.0/bk_releasenotes_ambari_2.1.0.0/content/amba... I hope you are using later ambari versions.

.

Are you using a kerberized environment?

From ambari host are you able to access the mentioned URL using curl/wget? (Without getting read timeout or Connection refused)

wget http://m2.hdp22:8744/api/v1/topology/summary?field=topologies
or 
curl http://m2.hdp22:8744/api/v1/topology/summary?field=topologies

.