EMR Spark - TransportClient: Failed to send RPC
I'm getting this error, I tried to increase memory on cluster instances and in the executor and driver parameters without success.
17/05/07 23:17:07 ERROR TransportClient: Failed to send RPC 6465703946954088562 to ip-172-30-12-164.eu-central-1.compute.internal/172.30.12.164:34706: java.nio.channels.ClosedChannelException
Does anyone have any clue to fix this error?
BTW I'm using YARN as cluster manager
Thanks in advance
Answer
Finally I resolved the problem. It was due to insufficient disk space. One column of hadoop logs showed:
Hadoop YARN: 1/1 local-dirs are bad: /var/lib/hadoop-yarn/cache/yarn/nm-local-dir; 1/1 log-dirs are bad: /var/log/hadoop-yarn/containers
Googling it I found http://gethue.com/hadoop-yarn-11-local-dirs-are-bad-varlibhadoop-yarncacheyarnnm-local-dir-11-log-dirs-are-bad-varloghadoop-yarncontainers/
"If you are getting this error, make some disk space!"
To see this error I have to activate the yarn logs in EMR. See
http://docs.aws.amazon.com/emr/latest/ManagementGuide/emr-web-interfaces.html
To have access to the logs port in the cluster ec2 instances I changed security groups for it
i.e.:
master instance was listening here: 172.30.12.84:8088 And core instance here: 172.30.12.21:8042
Finally I fixed the problem changing in etl.py the type of instances by other ones with bigger disks:
master: m3.2xlarge
core: c3.4xlarge