When using cgroups we require LCE to be configured in the cluster to start containers.
When LCE starts containers as the user that submitted the job. While this works correctly in a secure setup, in an un-secure setup this presents a couple issues:
- LCE requires all Hadoop users submitting jobs to be Unix users in all nodes
- Because users can impersonate other users, any user would have access to any local file of other users
Particularly, the second issue is not desirable as a user could get access to ssh keys of other users in the nodes or if there are NFS mounts, get to other users data outside of the cluster.