Hi all!
tl;dr newly created files in HDFS will not be 'world' readable by default.
I.e. you must be either the owner or in the file's group to read the file.
Today we changed the default HDFS umask to 027, so that all new files and
dirs will have either 640 (rw-r-—--) (for files) or 750 (rwx-r-x-—) for
directories.
We don't anticipate any problems, but if you encounter any please don't
hesitate to let us know. You can always hdfs dfs -chmod
<https://hadoop.apache.org/docs/r2.7.6/hadoop-project-dist/hadoop-common/FileSystemShell.html#chmod>
your files after you create them.
See
https://phabricator.wikimedia.org/T270629 for more info.
Your friendly Hadoop operators,
- Andrew & Razzi & Luca