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From Arshak Navruzyan <>
Subject documentation regarding WAL
Date Fri, 17 Jan 2014 23:53:43 GMT
I am wondering whether the following sections of the docs correctly
describe the current WAL behavior or are these remnants of the time when
the WAL was stored locally.

*2.8. Fault-Tolerance*

The Master will coordinate the copying of write-ahead logs to HDFS so the
logs are available to all tablet servers.
*11.10. Recovery*
Recovery is performed by asking the loggers to copy their write-ahead logs
into HDFS. As the logs are copied, they are also sorted, so that tablets
can easily find their missing updates. The copy/sort status of each file is
displayed on Accumulo monitor status page.

are these accurate or does each tserver directly write it's WAL to HDFS
(vs. having to copy it)?

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