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https://issues.apache.org/jira/browse/HDFS-9909?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Bogdan Raducanu updated HDFS-9909:
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    Attachment: Main.java

> Can't read file after hdfs restart
> ----------------------------------
>
>                 Key: HDFS-9909
>                 URL: https://issues.apache.org/jira/browse/HDFS-9909
>             Project: Hadoop HDFS
>          Issue Type: Bug
>          Components: hdfs-client
>    Affects Versions: 2.7.1
>            Reporter: Bogdan Raducanu
>         Attachments: Main.java
>
>
> If HDFS is restarted while a file is open for writing then new clients can't 
> read that file until the hard lease limit expires and block recovery starts.
> Scenario:
> 1. write to file, call hflush
> 2. without closing the file, restart hdfs 
> 3. after hdfs is back up, try to open file from reading from a new client
> Repro attached.
> Thoughts:
> * As far as I can tell this happens because the last block is RWR and 
> getReplicaVisibleLength returns -1 for this. The recovery starts after hard 
> lease limit expires (so file is readable only after 1 hour).
> * one can call recoverLease which will start the lease recovery sooner, BUT, 
> how can one know when to call this? The exception thrown is IOException which 
> can happen for other reasons.
> I think a reasonable solution would be to return a specialized exception 
> (similar to AlreadyBeingCreatedException when trying to write to open file).



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