I have a Spark Spark cluster where the master node is also the worker node. I can't reach the master from the driver-code node, and I get the error:
14:07:10 WARN client.AppClient$ClientEndpoint: Failed to coect to master master-machine:7077
The SparkContext in driver-code node is configured as: SparkConf conf = new SparkConf(true).setMaster(spark:master-machine//:7077);
I can successfully ping master-machine, but I can't successfully telnet master-machine 7077. Meaning the machine is reachable but the port is not.
What could be the issue? I have disabled Ubuntu's ufw firewall for both master node and node where driver code runs (client).