Github user EronWright commented on the issue:
https://github.com/apache/flink/pull/2864
@mxm I think the root cause was incorrectly diagnosed here, and as a result
this PR did the wrong thing. It is incorrect to bypass the UGI login methods
when in 'SIMPLE' auth mode.
For example, Flink uses the `HADOOP_USER_NAME` envvar to pass the client's
username from CLI to AppMaster to TaskManager; the HadoopSecurityContext must
be used to apply it. This PR wrecks havoc on scenarios like this.
I think the root cause in the MapR case is that MapR seems to rely on an
[actual JAAS config file](https://community.mapr.com/thread/9240), rather than
on stock Hadoop's in-memory JAAS configuration. The true solution may be to
merge the user-supplied JAAS with our in-memory defaults, thus obtaining the
`hadoop_simple` entry from `maps.login.conf`.
CC @tillrohrmann @vijikarthi
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at [email protected] or file a JIRA ticket
with INFRA.
---