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Date: Tue, 3 Jul 2012 11:25:06 +0530
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 <CALcs+N-ZJVhfKMvoi96gP8ucraxXv0Hp6BOwxt4==kaDj5eGSA@mail.gmail.com>
Subject: Re: WAL corruption
From: manoj p <eorstvz@gmail.com>
To: user@hbase.apache.org
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Hi bryan,

WAL is used only during minor compaction. During major compaction WAL is
not used.

Cheers,
Manoj.P

On Mon, Jul 2, 2012 at 11:00 PM, Bryan Keller <bryan@vancameron.net> wrote:

> During an upgrade of my cluster to 0.90 to 0.92 over the weekend, the WAL
> (files in the /hbase/.logs directory) was corrupted and it prevented HBase
> from starting up. The exact exception was "java.io.IOException: Could not
> obtain the last block locations" on the WAL files.
>
> I was able to recover by deleting the /hbase/.logs directory. My question
> is, if HBase had no pending updates, i.e. nothing writing to it, is there
> any risk of data loss by deleting the WAL directory? For example, does
> rebalancing, flushing, or compaction use the WAL or is the WAL used only
> for inserts/updates/deletes?
>
>

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