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https://issues.apache.org/jira/browse/HDFS-10348?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16104210#comment-16104210
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Hadoop QA commented on HDFS-10348:
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| (x) *{color:red}-1 overall{color}* |
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|| Vote || Subsystem || Runtime || Comment ||
| {color:blue}0{color} | {color:blue} reexec {color} | {color:blue}  0m  
0s{color} | {color:blue} Docker mode activated. {color} |
| {color:red}-1{color} | {color:red} patch {color} | {color:red}  0m  7s{color} 
| {color:red} HDFS-10348 does not apply to trunk. Rebase required? Wrong 
Branch? See https://wiki.apache.org/hadoop/HowToContribute for help. {color} |
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|| Subsystem || Report/Notes ||
| JIRA Issue | HDFS-10348 |
| JIRA Patch URL | 
https://issues.apache.org/jira/secure/attachment/12801965/HDFS-10348-1.patch |
| Console output | 
https://builds.apache.org/job/PreCommit-HDFS-Build/20452/console |
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> Namenode report bad block method doesn't check whether the block belongs to 
> datanode before adding it to corrupt replicas map.
> ------------------------------------------------------------------------------------------------------------------------------
>
>                 Key: HDFS-10348
>                 URL: https://issues.apache.org/jira/browse/HDFS-10348
>             Project: Hadoop HDFS
>          Issue Type: Bug
>          Components: namenode
>    Affects Versions: 2.7.0
>            Reporter: Rushabh S Shah
>            Assignee: Rushabh S Shah
>         Attachments: HDFS-10348-1.patch, HDFS-10348.patch
>
>
> Namenode (via report bad block nethod) doesn't check whether the block 
> belongs to the datanode before it adds to corrupt replicas map.
> In one of our cluster we found that there were 3 lingering corrupt blocks.
> It happened in the following order.
> 1. Two clients called getBlockLocations for a particular file.
> 2. Client C1 tried to open the file and encountered checksum error from   
> node N3 and it reported bad block (blk1) to the namenode.
> 3. Namenode added that node N3 and block blk1  to corrrupt replicas map   and 
> ask one of the good node (one of the 2 nodes) to replicate the block to 
> another node N4.
> 4. After receiving the block, N4 sends an IBR (with RECEIVED_BLOCK) to 
> namenode.
> 5. Namenode removed the block and node N3 from corrupt replicas map.
>    It also removed N3's storage from triplets and queued an invalidate 
> request for N3.
> 6. In the mean time, Client C2 tries to open the file and the request went to 
> node N3.
>    C2 also encountered the checksum exception and reported bad block to 
> namenode.
> 7. Namenode added the corrupt block blk1 and node N3 to the corrupt replicas 
> map without confirming whether node N3 has the block or not.
> After deleting the block, N3 sends an IBR (with DELETED) and the namenode 
> simply ignores the report since the N3's storage is no longer in the 
> triplets(from step 5)
> We took the node out of rotation, but still the block was present only in the 
> corruptReplciasMap. 
> Since on removing the node, we only goes through the block which are present 
> in the triplets for a given datanode.
> [~kshukla]'s patch fixed this bug via 
> https://issues.apache.org/jira/browse/HDFS-9958.
> But I think the following check should be made in the 
> BlockManager#markBlockAsCorrupt instead of 
> BlockManager#findAndMarkBlockAsCorrupt.
> {noformat}
> if (storage == null) {
>       storage = storedBlock.findStorageInfo(node);
>     }
>     if (storage == null) {
>       blockLog.debug("BLOCK* findAndMarkBlockAsCorrupt: {} not found on {}",
>           blk, dn);
>       return;
> }
> {noformat}



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