Steadfast has been distributing dedicated servers with in-built configurations for at least a decade now. Raid is a widely used technology but how it changed around the years with the advent of Solid state Drives(SSDs). We saw many people asking about Types of raid arrays, how it affects them. How they can get the best performance out of also keeping an eye on the bottom line. So, in this blog, we will talk about the things mentioned above. Here we go first with the Types of raid arrays.
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What is Raid?
Raid is Redundant Array of Inexpensive Disks. You can say that a Raid is way more logical way of putting multiple disks together into a single array. The idea behind raid is these multiple disks working together will have more speed and offer a relability of a more expensive disk. The different speed and relabilty which you will get depends on the types of raid arrays which you are using,
What are different types of raid arrays?
RAID 0 is taking any number of different disks and then merging them to form one large disk. What merging to disk will do is increase the speed as you are reading and writing from multiple disks at a time. When you stake them all together then one file can use the speed and capacity of all the drives of the array.
The only downside of having the RAID 0 is that it is not redundant. If you lose any stacked individual disk you will completely lose the data. This RAID type is very much less reliable than having a single disk.
RAID 1 (Mirroring)
RAID 1 is more complicated than RAID 0. It uses a pair of identical disks and it copies the data and distributes it equally across the drives in the array. This can be used in the case where you lose the drive. You can still stay up and running off the additional drive.
RAID 1 also gives you additional advantages of increased read performance and you can easily read data of any drives in the array.
RAID 5/6 (Striping + Distributed Parity)
It takes RAID 5 to use at least 3 drives and RAID 6 takes at 4 drives at once. RAID 5 takes the idea from RAID 0 and also strips the data across multiple drives to increase the performance. But the RAID 5 adds some things extra like adding redundancy which distributes parity information across all disks. You can check the internet to see the details of how these things happen. But for now, just understand in RAID 5 you can lose 1 disk and in RAID 6 you can lose 2 disks and still maintain operation.
Frankly speaking RAID 5 and RAID 6 are not the best options for a heavy write environment. For example, if you are using them on a database server. It is likely that it will hurt the overall server performance. If you lose a drive in RAID 5 or RIAD 6 then you have to sacrifice performance to keep your environment up and going.
Raid 10 (Mirroring + Stripping)
RAID 10 is a combination of RAID 0(striping) and RAID 1(mirroring). This will get you both speed and redundancy. This is one of the most recommended raids if you are looking for speed and redundancy as well. RAID 10 at least requires 4 drives to work. In a RAID 4, the 4 drives are divided into 2 parts where 2 hold half of the striped data. WHere as the other 2 hold another half of the striped data. This gives you a cushion where you can lose any drive and then 2nd drive and still won’t lose any data. Just like RAID 1, you’ll only have the capacity of half the drives, but you will see improved read and write performance. You will also have the fast rebuild time of RAID 1.
When should you use RAID?
RAID is very important for your business the backups will help you ensure no data loss in case of some catastrophic incident. It can take hours to restore a large amount of data if you experience drive failure. Those backups could be hours and days old and nothing is saved after that. You could lose everything after the last backup very easily. But RAID allows you to weather the storm and if you have few drive failures there won’t be any loss in the data.
Different type of RAID you should use?
- First No Raid: It is good if you are ok with losing several hours of downtime. And data loss while you restore your site from backups.
- Second Raid 0: It works better and it is good if the data is not that important. And can be lost but performance is critical.
- Third Raid 1: This one is good if you want to gain speed and also have data redundancy in place.
- Fourth Raid 5/6: This is good if you have good web servers and also high read environments or large storage of arrays stored as a single object.
- Fifth Raid 10: This is one we will recommend as this one provides an additional read and write speed as well as some additional redundancy.
Software vs Hardware?
There are options of Software Raid in all the Steadfast’s dedicated servers. Which means that there is no cost for software RAID 1 and it is highly recommended if you using a local storage. We recommend you that RAID drives should be of same type and size.
Whereas the Hardware RAID requires a controller installed in the server. There are engineers in the Steadfast who will recommend which hardware RAID is best for you. A hardware-based RAID card does all the management of the RAID array(s), providing logical disks. To the system with no overhead on the part of the system itself.
What RAID do not do ?
- RAID does not equate to 100% uptime: We just mean that nothing can do that. Raid is just a tool that helps you minimize downtime and availability issues.
- It does not replace all the backups: Well if you have well planned and frequently tested backup we think even raid can replace that.
- Raid does not allow you to increase the size: So, if you think you need more space you can not just add more disks which you can not do. You have to go and start again from the scratch.
- RAID isn’t always the best option for virtualization: Raid is not the best solution in terms of virtualization. In this case, you have to look at some other options like SAN.
Types of raid arrays here is everything you need to know about them. We explained everything about Raid. What is raid. what are different types of raid and which one is the best. Hope you find this information useful. Thank you for the read.