spark_ec2.py cannot find all slave instances. In particular:
- I created a master & slave and configured them.
- I created new slave instances from the original slave ("Launch More Like This").
- I tried to relaunch the cluster, and it could only find the original slave.
Old versions of the script worked. The latest working commit which edited that .py script is: a0bcbc159e89be868ccc96175dbf1439461557e1
There may be a problem with this PR: https://github.com/apache/spark/pull/1899.