Alert Error: Connection failed to http://xxxxxx:8042 (urlopen error timed out)

[#1]

We are frequently getting the below error on all datanodes and within some time it is rectifying itself.

Connection failed to http://xxxxxx:8042 (urlopen error timed out)

I checked the port 8042 on the datanode, but it is in Listening state only.

[#2]

Looks like alert is from NodeManager Health Summary This service-level alert is triggered if there are unhealthy NodeManagers. Can you provide value of property "yarn.nodemanager.health-checker.script.timeout-ms"?

[#3]

Hi Schhabra,

"yarn.nodemanager.health-checker.script.timeout-ms" value is '60000'

[#4]

Any resolution for this issue? I am stuck at this issue since a long time, ambari is not able to install services on all nodes.