I have heard this word tossed around the forum. I googled it but still didn't understand the meaning. Could someone explain this fundamentally for IT Beginners like myself. Maybe use an analogy. What is it? What does it do?
Do all computers have it? If it is important, what is it's importance.

So you want an analogy, would be far easier to just explain it but here goes,

Well its a bit like sex, one partner is good but two is obviously better (more complicated but definetlly better) thats raid explained.

Now to the two main types of raid,

Raid0 is like sex without a condom lot better and your finished quicker,

Raid1 sex with a condom nowhere near as good but its a damn sight safer.

Originally Posted by popeye67

So you want an analogy, would be far easier to just explain it but here goes,

Well its a bit like sex, one partner is good but two is obviously better (more complicated but definetlly better) thats raid explained.

Now to the two main types of raid,

Raid0 is like sex without a condom lot better and your finished quicker,

Raid1 sex with a condom nowhere near as good but its a damn sight safer.

Now you just made me mad. Thanks for nothing.

When you use your computer it reads and writes information on the hard drive, the quicker the computer can read and write that information the faster it will be,

with raid0 the computer has two drives to read and write to simultaniously which means theres a performance increase, drawbacks are cost (you need to buy another drive), if one drive fails you lose all the information on both drives, performance there is an improvment in performace but its not a marked improvment you can see with the naked eye, the gain is minimal and not really worth all the arseing around.

raid1 reads and writes simultaniously to both drives but its the same information, bit like backing up your entire hard drive as you go, if one hard drive suffers a complete failure all your info and the operating system is still intact on the other drive, drawbacks price still need two of em, hard drive failures tend not to be complete they tend to go bad over time, if one drive goes there no guarentee the other drive hasnt already gone, the only time you will find out is when you really need it, there are ways round this useing raid parity but its even more complicated and more expensive cos you need even more drives and finally i havent got a clue how its done so your on yor own,

most modern motherboards support raid, is it worth setting a raid array - probably not, is it worth learning how to set up a raid array - its either that or the ironing.

I come on this forum for three reasons, to learn, to help others and to have a laugh, it is actually rather a good analogy but if your offended just ignore it.

Originally Posted by popeye67

So you want an analogy, would be far easier to just explain it but here goes,

Well its a bit like sex, one partner is good but two is obviously better (more complicated but definetlly better) thats raid explained.

Now to the two main types of raid,

Raid0 is like sex without a condom lot better and your finished quicker,

Raid1 sex with a condom nowhere near as good but its a damn sight safer.

That shit was funny!!!. Some people miss your dry british humor, but I get a kick out of it and bob's your uncle!

RAID: Redundant Array of Independent Disks cards—Adapters that enable you to attach multiple drives and array them in different ways to improve reliability, redundancy, to improve reliability, redundancy, and/or performance. These cards require an onboard BIOS to enable the array to be bootable.

PATA/SATA RAID

RAID is an acronym for redundant array of independent (or inexpensive) disks and was designed to
improve the fault tolerance and performance of computer storage systems. RAID was first developed
at the University of California at Berkeley in 1987, and was designed so that a group of smaller, less
expensive drives could be interconnected with special hardware and software to make them appear as
a single larger drive to the system. By using multiple drives to act as one drive, increases in fault tolerance
and performance could be realized.
Initially, RAID was conceived to simply enable all the individual drives in the array to work together
as a single, larger drive with the combined storage space of all the individual drives added up, which
is called a JBOD (Just a Bunch of Disks) configuration. Unfortunately, if you had four drives connected
in a JBOD array acting as one drive, you would be four times more likely to experience a drive
failure than if you used just a single larger drive. And because JBOD does not use striping, performance
would be no better than a single drive either. To improve both reliability and performance, the
Berkeley scientists proposed six levels (corresponding to different methods) of RAID. These levels provide
varying emphasis on either fault tolerance (reliability), storage capacity, performance, or a combination
of the three.
Although it no longer exists, an organization called the RAID Advisory Board (RAB) was formed in
July 1992 to standardize, classify, and educate on the subject of RAID. The RAB developed specifications
for RAID, a conformance program for the various RAID levels, and a classification program for
RAID hardware.

The RAID Advisory Board defined seven standard RAID levels, called RAID 0–6. Most RAID controllers
also implement a RAID 0+1 combination, which is usually called RAID 10. The levels are as follows:

■ RAID Level 0: Striping

—File data is written simultaneously to multiple drives in the array,
which act as a single larger drive. This offers high read/write performance but very low reliability.
Requires a minimum of two drives to implement.

■ RAID Level 1: Mirroring

—Data written to one drive is duplicated on another, providing
excellent fault tolerance (if one drive fails, the other is used and no is data lost) but no real
increase in performance as compared to a single drive. Requires a minimum of two drives to
implement (same capacity as one drive).

■ RAID Level 2: Bit-level ECC

—Data is split one bit at a time across multiple drives, and error
correction codes (ECCs) are written to other drives. This is intended for storage devices that do
not incorporate ECC internally (all SCSI and ATA drives have internal ECC). It’s a standard that
theoretically provides high data rates with good fault tolerance, but seven or more drives are
required for greater than 50% efficiency, and no commercial RAID 2 controllers and/or drives
without ECC are available.

■ RAID Level 3: Striped with parity

—Combines RAID Level 0 striping with an additional
drive used for parity information. This RAID level is really an adaptation of RAID Level 0 that
sacrifices some capacity, for the same number of drives. However, it also achieves a high level of
data integrity or fault tolerance because data usually can be rebuilt if one drive fails. Requires a
minimum of three drives to implement (two or more for data and one for parity).

■ RAID Level 4: Blocked data with parity

—Similar to RAID 3 except data is written in
larger blocks to the independent drives, offering faster read performance with larger files.
Requires a minimum of three drives to implement (two or more for data and one for parity).

■ RAID Level 5: Blocked data with distributed parity

—Similar to RAID 4 but offers
improved performance by distributing the parity stripes over a series of hard drives. Requires a
minimum of three drives to implement (two or more for data and one for parity).

■ RAID Level 6: Blocked data with double distributed parity

—Similar to RAID 5 except
parity information is written twice using two different parity schemes to provide even better
fault tolerance in case of multiple drive failures. Requires a minimum of four drives to implement
(two or more for data and two for parity).
There are also nested RAID levels created by combining several forms of RAID. The most common are
as follows:

■ RAID Level 01: Mirrored stripes

—Drives are first combined in striped RAID 0 sets, then the
RAID 0 sets are mirrored in a RAID 1 configuration. A minimum of four drives is required, and
the total number of drives must be an even number. Most PC implementations allow four
drives only. The total usable storage capacity is equal to half of the number of drives in the
array times the size of the lowest capacity drive. RAID 01 arrays can tolerate a single drive failure
and some (but not all) combinations of multiple drive failures. Not generally recommended
because RAID 10 offers more redundancy and performance.

■ RAID Level 10: Striped mirrors

—Drives are first combined in mirrored RAID 1 sets, then the
RAID 1 sets are striped in a RAID 0 configuration. A minimum of four drives is required, and the
total number of drives must be an even number. Most PC implementations allow four drives
only. The total usable storage capacity is equal to half of the number of drives in the array times
the size of the lowest capacity drive. RAID 10 arrays can tolerate a single drive failure and many (but not all) combinations of multiple drive failures. Similar to RAID 01, except with somewhat
increased reliability because more combinations of multiple drive failures can be tolerated, and
rebuilding an array after a failed drive is replaced is much faster and more efficient.
Additional custom or proprietary RAID levels exist that were not originally supported by the RAID
Advisory Board. For example, from 1993 through 2004, “RAID 7” was a trademarked marketing term
used to describe a proprietary RAID implementation released by the (now defunct) Storage Computer
Corp.
When set up for maximum performance, arrays typically run RAID Level 0, which incorporates data
striping. Unfortunately, RAID 0 also sacrifices reliability such that if any one drive fails, all data in the
array is lost. The advantage is in extreme performance. With RAID 0, performance generally scales up
with the number of drives you add in the array. For example, with four drives you won’t necessarily
have four times the performance of a single drive, but many controllers can come close to that for
sustained transfers. Some overhead is still involved in the controller performing the striping, and
issues still exist with latency—that is, how long it takes to find the data—but performance will be
higher than any single drive can normally achieve.
When set up for reliability, arrays generally run RAID Level 1, which is simple drive mirroring. All
data written to one drive is written to the other. If one drive fails, the system can continue to work on
the other drive. Unfortunately, this does not increase performance at all, and it also means you get to
use only half of the available drive capacity. In other words, you must install two drives, but you get
to use only one (the other is the mirror). However, in an era of high capacities and low drive prices,
this is not a significant issue.
Combining performance with fault tolerance requires using one of the other RAID levels, such as
RAID 5 or 10. For example, virtually all professional RAID controllers used in network file servers are
designed to use RAID Level 5. Controllers that implement RAID Level 5 used to be very expensive,
and RAID 5 requires that at least three drives must be connected, whereas RAID 10 requires four
drives.
With four 500GB drives in a RAID 5 configuration, you would have 1.5TB of total storage, and you
could withstand the failure of any single drive. After a drive failure, data could still be read from and
written to the array. However, read/write performance would be exceptionally slow, and it would
remain so until the drive was replaced and the array was rebuilt. The rebuild process could take a relatively
long time, so if another drive failed before the rebuild completed, all data would be lost.
With four drives in a RAID 10 configuration, you would have only 1TB of total storage. However, you
could withstand many cases of multiple drive failures. In addition, after a drive failure, data could still
be read from and written to the array at full speed, with no noticeable loss in performance. In addition,
once the failed drive is replaced, the rebuild process would go relatively quickly as compared to
rebuilding a RAID 5 array.

Because of the advantages of RAID 10, many are recommending it as an
alternative to RAID 5 where maximum redundancy and performance are required.
A typical low-cost SATA RAID controller enables up to four, six, or eight drives to be attached, and
you can run them in RAID Level 0, 1, 5, or 10 mode. Parallel ATA RAID cards are available, but most
RAID cards have moved to Serial ATA, which doesn’t have the master/slave channel-sharing problems
of Parallel ATA. Serial ATA RAID cards use a separate Serial ATA data channel (cable) for each drive,
allowing maximum performance. Motherboard-based RAID controllers almost exclusively use SATA drives.

If you are considering a SATA RAID controller (or a motherboard with an integrated SATA RAID controller),
here are some things to look for:
■ RAID levels supported. (Most support 0, 1, 5, and 10. A lack of RAID 5 and/or RAID 10 support
indicates a very low-end product.)
■ Support for four, six, or eight drives.
■ Support for 3Gbps or 6Gbps Serial ATA transfer rates.
■ PCIe bus interface for best performance and future compatibility.
Some operating systems include software-based RAID capability; however, I don’t generally recommend
using it because of performance issues. Normally if you want both performance and reliability,
you should look for Serial ATA RAID controllers that support RAID Level 5 or 10.

Originally Posted by popeye67

When you use your computer it reads and writes information on the hard drive, the quicker the computer can read and write that information the faster it will be,

with raid0 the computer has two drives to read and write to simultaniously which means theres a performance increase, drawbacks are cost (you need to buy another drive), if one drive fails you lose all the information on both drives, performance there is an improvment in performace but its not a marked improvment you can see with the naked eye, the gain is minimal and not really worth all the arseing around.

raid1 reads and writes simultaniously to both drives but its the same information, bit like backing up your entire hard drive as you go, if one hard drive suffers a complete failure all your info and the operating system is still intact on the other drive, drawbacks price still need two of em, hard drive failures tend not to be complete they tend to go bad over time, if one drive goes there no guarentee the other drive hasnt already gone, the only time you will find out is when you really need it, there are ways round this useing raid parity but its even more complicated and more expensive cos you need even more drives and finally i havent got a clue how its done so your on yor own,

most modern motherboards support raid, is it worth setting a raid array - probably not, is it worth learning how to set up a raid array - its either that or the ironing.

Who would use something like this? I am guessing your normal, everyday computer user wouldn't need it.

Originally Posted by popeye67

I come on this forum for three reasons, to learn, to help others and to have a laugh, it is actually rather a good analogy but if your offended just ignore it.

I laugh and get a kick out of your analogys most of the time (Way you have to look at it is you dont need a degree in electronics or need to know how to run a nuclear power station to change a lightbulb, you just stick the bulb in the socket that is made specifically for it, lot You have a certain knack that I can appreciate. And you have used your analogys to explain things to me which have been a great help.

This was meant to be rude and crude. Don't do it again. Not in my Thread. I guess that is the difference in our countries. If I had gotten an e-mail like this in the real corporate world it could be misconstrued as sexual harrasment. That is the way it is in my world. I have said what I needed to say. Lets forget it because I really would like us to be friends and move on.