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Subject: =?windows-1252?Q?Re=3A_Question_about_Name_Spaces=85_?=
From: Michael Segel <michael_segel@hotmail.com>
In-Reply-To: <943DB4E9-848E-456D-A30D-F9D5FF4EA291@yahoo.com>
Date: Wed, 15 May 2013 09:38:18 -0500
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 <943DB4E9-848E-456D-A30D-F9D5FF4EA291@yahoo.com>
To: user@hadoop.apache.org

Well...=20

On the one hand, I'm trying to understand why one would break a cluster =
in to multiple name spaces.=20
(Obviously this gets back to managing very large clusters.)=20

On the other. Why would someone want to have a copy of a file in two =
different name spaces?=20

I'm making an assumption that when we have 3x replication that the =
replicas don't cross name space boundaries. (Is this correct?)

My take is that one would copy a file to a second name space because =
they want a physical copy in both name spaces for redundancy in case a =
name space goes down. They would do this only for mission critical =
files, or if the data is being shared by two different groups who want =
their own copy of the data and they work solely within a single name =
space.=20

The reason I am asking is that I'm trying to see how people view and use =
namespaces.=20

Does that make sense?=20

Thx


On May 15, 2013, at 9:24 AM, Lohit <lohit.vijayarenu@yahoo.com> wrote:

>=20
>=20
> On May 15, 2013, at 7:17 AM, Michael Segel <michael_segel@hotmail.com> =
wrote:
>=20
>> Quick question...
>> So when we have a cluster which has multiple namespaces (multiple =
name nodes) , why would you have a file in two different namespaces?=20
>>=20
> Are you saying why one would create same file in two namespace? Or are =
you saying is there an option to have only one file but in two =
namespace?=20
>=20
> Could you rephrase or give more information=20
>>=20
>=20