I'm trying to run Docker on Elastic MapReduce streaming but am having trouble with a permissions issue. In my bootstrap script, I need the "hadoop" user to be part of the "docker" group (as described on the AWS Docker Basics page):
sudo usermod -a -G docker hadoop
but I cannot log out or spawn a subshell (with newgrp). Is there a way to force the group setting to take effect in my current shell session?