Trouble accessing Kubernetes endpoints
I’m bringing up Spark on Kubernetes according to this example: https://github.com/kubernetes/kubernetes/tree/master/examples/spark
For some reason, I’m having problems getting the master to listen on
:7077 for connections from worker nodes. It appears that connections aren’t being proxied down from the service. If I bring the service up, then bring the master controller up with the
$SPARK_MASTER_IP set to spark-master, it correctly resolves to the service IP but cannot bind the port. If I set the ip to localhost instead, it binds a local port and comes up
-- since services should forward socket connections down to the pod endpoint this should be fine, so we move on.
Now I bring up workers. They attempt to connect to the service IP on
:7077 and cannot. It seems as if connections to the service aren’t making it down to the endpoint. Except…
I also have a webui service configured as in the example. If I connect to it with kubectl –proxy I can get down to the web service that’s served on
:8080 from spark-master, by hitting it through the webui service. Yet the nearly identically-configured spark-master service on
port 7077 gives no love. If I configure the master to bind a local IP, it comes up but doesn’t get connections from the service. If I configure it to bind through the service, the bind fails and it can’t come up at all.
I’m running out of ideas as to why this might be happening
-- any assistance is appreciated. I’m happy to furnish more debugging info on request.
One Solution collect form web for “Trouble accessing Kubernetes endpoints”
I’m sorry, the Spark example was broken, in multiple ways.
It now works, as of 2/25/2016, and is passing our continuous testing, at least at HEAD (and the next Kubernetes 1.2 release).
Note that DNS is required, though it is set up by default in a number of cloud provider implementations, including GCE and GKE.