[
https://issues.apache.org/jira/browse/HDFS-12996?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16317342#comment-16317342
]
Rushabh S Shah commented on HDFS-12996:
---------------------------------------
[~hanishakoneru]: Looks like a good improvement. Thanks for the design.
I skimmed through the design document. I have couple of questions.
1. Suppose user1 and user2 deleted some of their directories (lets say dir1 and
dir2 respectively).
If user1 wants to recover its directory, then we will recover dir2 as well ?
2. Another scenario I am concerned about:
Many of our clients(lets say user1) use {{/tmp/<userId>}} to store their
intermediate task output (to work around quota problems).
After a job completes, they delete this space and use the same location to
store next job output.
In the meantime if some other user(lets say user2) wants to recover their
mistakenly deleted directory then we will go back in time for user1 which might
corrupt user1's output directory.
Also the design looks very similar to Checkpointing/Snapshots.
> DataNode Replica Trash
> ----------------------
>
> Key: HDFS-12996
> URL: https://issues.apache.org/jira/browse/HDFS-12996
> Project: Hadoop HDFS
> Issue Type: New Feature
> Reporter: Hanisha Koneru
> Assignee: Hanisha Koneru
> Attachments: DataNode_Replica_Trash_Design_Doc.pdf
>
>
> DataNode Replica Trash will allow administrators to recover from a recent
> delete request that resulted in catastrophic loss of user data. This is
> achieved by placing all invalidated blocks in a replica trash on the datanode
> before completely purging them from the system. The design doc is attached
> here.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
