Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
MapReduce >> mail # user >> how to corrupt a replica of a block by manually?


Copy link to this message
-
Re: how to corrupt a replica of a block by manually?
Hmmm.. I guess that you can try to read this file using

$ hadoop fs -cat <file-with-corrupt-replica> to detect that

When reading a file its checksums are calculated and compared to checksums
that were calculated during a write operation. If verification fails, NN is
notified about the corrupt replica and you will fetch a different replica
from another DN to read that file.
2013/12/12 ch huang <[EMAIL PROTECTED]>

> hi,maillist:
>         what is the sample way to corrupt a replica of a block ,i opened a
> replica data file ,and delete a line,than use fsck ,nothing corrupt,
>  should the DN  be restarted?
>