RAID

[tomi832]

what's Raid exactly? I've seen that all of the AM4 mother boards have it while only the "high-end" ones at LGA 1151 has it...so what's the deal? and is it worth the money or just something a bit nice?

[Anghammarad]

Raid - Redundant Array of independent Disks =) 

 

Most mainboards today have this feature. 

 

If you want to build a home NAS or server, RAID would be good to have. For a daily use computer, gaming machine, I won't put raid on the list of things I want to have normally. 

 

Even though, if you make a stripe set (Raid 0) of 2 SSD you gain a little performance. But even then. Raid 0 isn't the way to go, because of the vulnerability.

[tomi832]

2 minutes ago, Anghammarad said:

Raid - Redundant Array of independent Disks =) 

 

Most mainboards today have this feature. 

 

If you want to build a home NAS or server, RAID would be good to have. For a daily use computer, gaming machine, I won't put raid on the list of things I want to have normally. 

 

Even though, if you make a stripe set (Raid 0) of 2 SSD you gain a little performance. But even then. Raid 0 isn't the way to go, because of the vulnerability.

 

what's the vulnerability? and all of the AM4 boards come with it from what I've seen so is it bad? also, you need to activate it through the BIOS or something like that?

[Anghammarad]

when you build a raid 0 of 2 or more disks/ssd and one gets damaged, all data on all disks used in that set is gone.

 

Meaning, one error all goes kabloooey

 

To get performance and security, even if more expensive is building a raid 10 array.

 

2 Raid 1 arrays put into a raid 0. So you can have 2 dying drives at the best if one in each raid 1 array and still have a working raid 0.

[tomi832]

1 minute ago, Anghammarad said:

when you build a raid 0 of 2 or more disks/ssd and one gets damaged, all data on all disks used in that set is gone.

 

Meaning, one error all goes kabloooey

 

oh...ok. so how is it good?

[Oshino Shinobu]

RAID = Redundant Array of Independent Disks/Drives. 

 

It is primarily used as a way to provide some data redundancy so that if a drive dies you don't lose all of your data. There are several different versions of RAID, each with different benefits and drawbacks. The main ones:

 

RAID 0: While technically not RAID as it doesn't provide any redundancy, it is still classed as such. In RAID 0, data is split (striped is a more accurate term) across all the drives in the array. It improves read and write performance, though all data on the array is lost if any of the drives fail. Unlike other versions of RAID, RAID 0 actually increases your chances of losing data. RAID 0 requires a minimum of 2 drives and can theoretically span across an unlimited number of drives (obviously, practicality limitations will come in to play, so don't expect to have 1000s of drives in RAID 0). Capacity of the array is the capacity of the smallest drive in the array multiplied by the number of drives in the array. 

 

RAID 1: Simple mirroring. All data is written to all drives in the array, so as long as one drive in the array remains, you do not lose data. Like RAID 0, it requires at least 2 drives and can theoretically scale infinitely. As all data is written to all drives, the capacity is that of the smallest drive in the array. RAID 1 becomes very cost inefficient when you add more than a few of drives. Personally, I wouldn't advise anything over 3 drives for RAID 1. 

 

RAID 10: Basically RAID 1+0. It operates in the same way as RAID 0, but each stripe of data is mirrored via RAID 1. RAID 1 requires at least 4 drives but becomes pretty cost inefficient when going much over that. 

 

RAID 5: Data is striped across the drives, along with a recovery/parity partition on each drive. You can lose any drive and then add a new one back in to rebuild the array. You cannot lose two drives at once without losing data. RAID 5 requires at least 3 drives but it is generally considered too inefficient with less than 4 drives. Capacity is that of the smallest drive multiplied by the number of drives minus 1 drive. 

 

RAID 6: Like RAID 5 but with double parity, so you can lose any two drives at a time. Requires 4 drives or more. Capacity is the same as RAID 5 but minus 2 drives. 

 

EDIT: RAID 2, 3 and 4 are also a thing, but are not as commonly used. This is a good article to read: http://searchstorage.techtarget.com/definition/RAID

[Anghammarad]

The usual simple raid controllers offer different raid types. 

 

For maximum space and the option of one drive faulting you'll go for Raid 5 configuration. A simple rule setting up a raid 5 is being able to divert the number of drives with 8. The smallest number of drives on that should be 4. then 8, 16, 24 etc. The more drives the more IO Performance.

 

Like I said earlier, Raid systems are mostly used in enviroments, where reliability of a system is needed. Though a Raid system won't spare you from making backups.

 

A few years ago only expensive mainboards got extra raid controllers, else if you wanted RAID, you needed to buy an extra controller to plug in. 

 

Today most Mobos have Raid already built in their chipset. So when your mobo has it, no worries, you don't need to use it, if it hasn't you just can't use it without an additional controller card.

[Oshino Shinobu]

Also, as a note on RAID vs backups, RAID is not an alternative to a backup solution. The recent WannaCry outbreak proves how valuable backups actually are. If you have to choose between RAID or a backup, go for the backup. RAID is primarily useful where downtime is not something that can be tolerated. If data integrity is your primary concern, periodical backups is the best solution.