Storage Foundations

Storage is a System which allows the data to be stored on multiple disks and provide high availability for accessing data in event of disk failure ,with the help of RAID mechanisam..There are many benefits of using storage system in IT organisation,.Let us get familiar with Storage systems available in industry ...

Agenda :
Storage Architecture
Storage Components
SAN ( IP,FC,FCOE)
Multi Protocol SAN
NAS( CIFS,NFS)
Unified Storage and Its Benefits
Drive Comparision

Storage Architecture














Storage Components

A storage also called as a SAN ( storage Area Networking) consists of below components

Frontend Connectivity : Frontend connectivity of a SAN is where the servers /Host are connected either directly or through the SAN switch

Backend Connectivity : Backend Connectivity of a SAN connects to drive enclosures which house the hard disk drives for storing data

Cache : often Cache is mirrored in a dual controller system for high availability

Drive Enclosure : Is a hardware which houses 12 , 15 or 25 hard disks drives within an enclosure depending on the SAN controller architecture or support

Frontend and Backend Protocols and Speeds





Storage benefits :
Shared storage allows better utilization
Server & Data consolidation
Enhanced Application Performance ,since the server is offloaded from disk I/o read writes, RAID, parity calculations
Support for Local replication which allows for :
Online Backup
MIS & Reporting
Application Development
Training etc.
Disaster Recovery capabilities



SAN (IP,FC,FCOE)

IP SAN


Frontend is always an iSCSI host ports with either 1 Gb/sec or 10 Gb/sec speed
Backend ports are either FC ( 4 Gb/sec) or SAS 1.0 ( 3 Gb/sec) or SAS 2.0 ( 6 Gb/sec) speed
Disk drives : Depending on backend drive support changes
IF SAS 1.0 is backend, the system supports SAS and SATA 3 Gb/sec drives
IF SAS 2.0 is backend ,the system supports SAS, NL SAS and SSD 6 Gb/sec drives
IF FC is backend , the system supports FC, SATA, and SSD 4 Gb/sec drives

FC SAN


Frontend is always an Fibre channel host ports with either 4 Gb/sec or 8 Gb/sec speed
Backend ports are either FC ( 4 Gb/sec) or SAS 1.0 ( 3 Gb/sec) or SAS 2.0 ( 6 Gb/sec) speed
Disk drives : Depending on backend drive support changes
IF SAS 1.0 is backend, the system supports SAS and SATA 3 Gb/sec drives
IF SAS 2.0 is backend ,the system supports SAS, NL SAS and SSD 6 Gb/sec drives
IF FC is backend , the system supports FC, SATA, and SSD 4 Gb/sec drives

FCOE SAN



Frontend is always an Fibre channel over Ethernet (FCOE) host ports 10 Gb/sec speed
Backend ports are either FC ( 4 Gb/sec) or SAS 1.0 ( 3 Gb/sec) or SAS 2.0 ( 6 Gb/sec) speed
Disk drives : Depending on backend drive support changes
IF SAS 1.0 is backend, the system supports SAS and SATA 3 Gb/sec drives
IF SAS 2.0 is backend ,the system supports SAS, NL SAS and SSD 6 Gb/sec drives
IF FC is backend , the system supports FC, SATA, and SSD 4 Gb/sec drives

Multi Protocol SAN



Frontend of Multiprotocol system can provide all i.e. iSCSI, FC, and FCOE Frontend host ports
Backend ports are either FC ( 4 Gb/sec) or SAS 1.0 ( 3 Gb/sec) or SAS 2.0 ( 6 Gb/sec) speed
Disk drives : Depending on backend drive support changes
IF SAS 1.0 is backend, the system supports SAS and SATA 3 Gb/sec drives
IF SAS 2.0 is backend ,the system supports SAS, NL SAS and SSD 6 Gb/sec drives
IF FC is backend , the system supports FC, SATA, and SSD 4 Gb/sec drives

Network Attached Storage

NAS is an IP based storage which provides file sharing capabilities ,It allows users to store and retrieve files in central location and also provide Data availability through RAID .A frontend of NAS is connected to the LAN ( Ethernet switch)

In NAS ,there are two File level protocols which allows the file sharing in a NAS


CIFS : Common Internet File System ,this protocol allows Windows clients/users to share ,store and retrieve files on a NAS device



NFS : Network File System ,this protocol allows Unix clients/users to share, store and retrieve files on a NAS device

A NAS can be implemented in two types


Gateway NAS :This model is Useful when there is an existing SAN already with the customer and wants to add NAS functionalilty ( generally this model requires a seperate SAN and doesnot have disks /storage within the gateway)


Integrated NAS : Useful when customer is looking at an integrated NAS which has its own storage ( generally this model has disks /storage of itself)





Gateway NAS



---> A NAS Gateway connects to the LAN using the IP ports on its frontend
---> However a NAS Gateway doesnot have any integrated disks or storage within in itself ,
---> A NAS Gateway through its FC backend connects to a frontend of an FC SAN either through a switch directly
---> A NAS gateway converts a File level requests into a block level requests to store and retrieve data from the SAN
---> In this model SAN stores the data ,perform RAID and parity calculation and NAS gateway does only file sharing and all block level read write operations are offloaded to SAN controllers


Integrated NAS








A Integrated NAS connects to the LAN using the IP ports on its frontend
It has integrated disks or storage within in itself and RAID is also performed by the same controller
An Integrated NAS does 2 major operations :
converts a File level requests into a block level requests
also read write operations of storing and retrieving data from the disk drives connected to it through the drive enclosure