SAN storage

SAN (Storage Area Network):

Why SAN?

How many drives your standalone PC can have?
ans: 2-3

Is that enough for the organization?
ans: of course not

If you lose your drive, what happens?
ans: total disaster, u lose all your data

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ok then, SAN has all the solution...
Make Storage section consisting huge array of drives and allocate LUNs (Logical Unit Number) to the clients as per they demand.
Like One of my client need 2 GB for rootvg of AIX server. Then I allocate 1 LUN of 2 GB and give to the client.

Following is the connection configuration in SAN:

[100s of clients]-----HIGH SPEED FIBRE CHANNEL----[Tera byte storage]

Clients get access to their LUN via Fibre Channel and thus can be said that they are physically connected.

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For Redundancy RAID is implemented

RAID 0 --- striping (for high performance)
RAID 1 --- mirroring (for safe side operation i.e even a single drive fails, u still have another as backup)
RAID 5 --- parity bit enabled (data recovery even if one disk failed)

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What about NAS?
NAS is similar thing, but it uses Ethernet instead of Fibre Channel. So NAS is slower than SAN.

Following is the connection configurtion in NAS

[CLIENTS]------ETHERNET---------[SERVER]------------[STORAGE]

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