Storage

Basic Disks – partition – primary partition – extended – Logical partitions

Dynamic disks: simple volume – spanned volume – stripped volume – mirrored volume – RAID – 5v

Basic Disk:

These are referred to partitions.
Using basic disks we can create partitions like primary, extended, logical.
Basic disks are useful for providing backward compatibility with older OS. Like DOS, 95, 98 etc..

Basic disks are useful while implementing clustering and when we want to have dual OS in our computers.

Basic disks can have 1primary, 1 extended and logical partition
Or four primary or 3 primary 1 extended and so on.

Basic disks can be converted to dynamic disks
For converting it requires 1MB of free space.

Conversion of basic disk to dynamic:

We can convert form basic to dynamic but not vice versa.
Possible when we get advanced

Converting from basic to Dynamic: (requires 1MB of free space):

Go to disk management
Right click on the disk1
Convert to dynamic disk.

Volume: 

Volume is made up of free space club or merged from more than one H.D. volumes avoid using of multiple drive letters or drives.
Easy to administer

Dynamic volume:

Dynamic disks refer to volumes. Using dynamic disks we can implement and extend volumes and implement raid.
Dynamic disk can be attached or detached on the file.


Simple Volumes: 

Simple volumes are similar to partitions which can be created only one Hard disk which do not offer fall tolerance.

Spanned Volume:

A volume can be created by selecting the free space from more than 1 Hdd

Span volumes offer extending of volume.
Do not offer fall tolerance
Maximum 32 Hdds
Min 2 Hdds

Creating simple volumes:

Open disk management
Right click on the black bar
New – volume
Select simple volume
Alter the space – next
Drive letter
File system
Check box perform quick format
Next – finish

Creating a spanned volume:

Open disk management
Right click on black bar
New volume
Select span – next
Select disk1&2 reduce &specify the size.
Drive letter – next
Perform – quick format – finish

Extending volume:

Right click on the volume we want to extend
Extend volume - next
Select the drive on which we want to extend the volume
Specify the size - next – finish

RAID: (Redundancy Array Inexpensive Disks or Independent disks)

Raid offers fall tolerance

Fault Tolerance: 

It is a technique used for protecting data against hardware failures.

Software RAID: 

It can be implemented from the OS. Which is not a guaranteed fault tolerance?

Hardware RAID: 

Can be implemented above the O.S. including the OS is protected.
Offers highest fault tolerance.

There are five RAID levels

RAID 0, 1, 2, 3, 4 and 5 these are supported by NT/2000/2003

RAID 0: striping without parity

Striped volumes:

Requires min 2 Hdds, max 32 Hdds.
Offers no fault tolerance
Suitable when performance is criteria.
Data is written evenly on to all drives
If any one of the drives fails whole data is lost.
Space selected on all the drives should be of identical size.

RAID 1 or Disk mirroring:

Requires min.2Hdds max.also 2 Hdds
Offers fall tolerance
Data is written onto both the drives simultaneously.
If one drive fails data is still available in the second drive.
I/P performance: reading is fast and writing is slow.

Implementation of mirror:

Create a simple volume ex: 100mb
Right click on S.V. and add mirror

Break mirror: 

Breaks the mirror and retains the partition and data and changes the drive letter
Right click on desired drive
Select break mirror

Remove mirror: 

Removes the mirrored volume.

If we want to break or remove the volume
Right click on mirror volume
Select break or remove

RAID 5 Striping with parity:

Requires min 3Hdds max 32 Hdds.
Offers highest fault tolerance
Data is written evenly on to all member striped volumes and
Parity information is also added.

Parity bit: It is mathematical calculation added to every piece of data and used for regenerating the data when any HDD fails.
Offers performance and availability
I/O performance: Reading and writing both are fast.

Mounting:

It is a feature of 2000 & 2003 used for accessing free space on the hard drive through a folder when drive letters get exhausted.

Using mounting:

open disk management
Create a simple volume
While creating select mount in the following MT, NTFS folder
Browse – new folder (create a folder here) – next – quick format – next
Finish

Accessing the Free space through a mount point:

Open the drive where we’ve created the folder.
We find here folder name with a drive icon