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Message-ID: <4aa34eb70808092248m1cbd941cg16057e50f17895a5@mail.gmail.com>
Date: Sat, 9 Aug 2008 21:48:17 -0800
From: "Dhruba Borthakur" <dhruba@gmail.com>
To: core-user@hadoop.apache.org
Subject: Re: What will happen if two processes writes the same HDFS file
Cc: hadoop-user@lucene.apache.org
In-Reply-To: <4751f7df0808092130h56afd5ffx5a67616bafb14d7@mail.gmail.com>
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References: <4751f7df0808092130h56afd5ffx5a67616bafb14d7@mail.gmail.com>

When the first one contacts the namenode to open the file for writing,
the namenode records this info in a "lease". When the second process
contacts the namenode to  open the same file for writing, the namenode
sees that a "lease" already exists for the file and rejects the
request from the second process.


On Sat, Aug 9, 2008 at 8:30 PM, 11 Nov. <nov.eleventh@gmail.com> wrote:
> IMHO, there must be one process that fails the write.
>