[HDFS-11197] Listing encryption zones fails when deleting a EZ that is on a snapshotted directory - ASF JIRA

Voters

Stop watching

Watchers

Create sub-task

Link

Clone

Update Comment Author

Replace String in Comment

Update Comment Visibility

Delete Comments

XML

Word

Printable

JSON

Details

Type: Bug
Status: Resolved
Priority: Minor
Resolution: Fixed
Affects Version/s: 2.6.0
Fix Version/s: 2.8.0, 3.0.0-alpha2
Component/s: hdfs
Labels:
None

Hadoop Flags:

Reviewed

Description

If a EZ directory is under a snapshotable directory, and a snapshot has been taking, then if this EZ is permanently deleted, it causes hdfs crypto listZones command to fail without showing any of the still available zones.

This happens only after the EZ is removed from Trash folder. For example, considering /test-snap folder is snapshotable and there is already an snapshot for it:

$ hdfs crypto -listZones
/user/systest           my-key
/test-snap/EZ-1       my-key

$ hdfs dfs -rmr /test-snap/EZ-1
INFO fs.TrashPolicyDefault: Moved: 'hdfs://ns1/test-snap/EZ-1' to trash at: hdfs://ns1/user/hdfs/.Trash/Current/test-snap/EZ-1

$ hdfs crypto -listZones
/user/systest           my-key
/user/hdfs/.Trash/Current/test-snap/EZ-1  my-key 

$ hdfs dfs -rmr /user/hdfs/.Trash/Current/test-snap/EZ-1
Deleted /user/hdfs/.Trash/Current/test-snap/EZ-1

$ hdfs crypto -listZones
RemoteException: Absolute path required

Once this error happens, hdfs crypto -listZones only works again if we remove the snapshot:

$ hdfs dfs -deleteSnapshot /test-snap snap1
$ hdfs crypto -listZones
/user/systest           my-key

If we instead delete the EZ using skipTrash option, hdfs crypto -listZones does not break:

$ hdfs crypto -listZones
/user/systest           my-key
/test-snap/EZ-2  my-key

$ hdfs dfs -rmr -skipTrash /test-snap/EZ-2
Deleted /test-snap/EZ-2

$ hdfs crypto -listZones
/user/systest           my-key

The different behaviour seems to be because when removing the EZ trash folder, it's related INode is left with no parent INode. This causes EncryptionZoneManager.listEncryptionZones to throw the seen error, when trying to resolve the inodes in the given path.

Am proposing a patch that fixes this issue by simply performing an additional check on EncryptionZoneManager.listEncryptionZones for the case an inode has no parent, so that it would be skipped on the list without trying to resolve it. Feedback on the proposal is appreciated.