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Accumulo >> mail # user >> What happens when tablet is 'lost'?

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Re: What happens when tablet is 'lost'?
Responding inline


Sent from my phone, so pardon the typos and brevity.
On Aug 9, 2012 9:02 AM, "Hugh Xedni" <[EMAIL PROTECTED]> wrote:
> Keith,
> From your response...
> "A tablets persistent data is composed of a set of files in HDFS and a
set of write ahead logs."
> "As long as the other tablet server can read the write ahead logs and
HDFS files, no data is lost."
> Question.
> I understand when a write arrives at a TabletServer it is written to a
Write-Ahead Log and then stored in the MemTable until flusing to HDFS via
minor compaction.
> 1) Are write ahead logs even used when data is bulk inserted into hdfs
then handed to Accumulo?

Only for the metadata entries regarding that table and those files.

> 2) If not, how is data replication achieved when using bulk insert

Hdfs replicates the data, so when the files are created in hdfs they are
> --
> Thank you,
> Hugh Xedni
> On Thu, Jul 26, 2012 at 12:31 PM, David Medinets <[EMAIL PROTECTED]>
>> Thanks, Keith. That explanation is just what I wanted.