Software RAID or Hardware RAID? What to choose?

Question

Hard disks

Good day.
I would be very grateful to you if you tell me which RAID is better to choose and why?
Software or Hardware? Can I create Software RAID 10?
1) As I understand it with Hardware, there is a risk that if the RAID controller fails, there is a possibility of losing all data due to the fact that the disk cannot be connected via USB to a new server and simply read the files.
2) As far as I understand Software RAID creates a certain load on the server itself? How perceptible is it? Should she be afraid?
3) Is it possible to create Software RAID 10 and is it worth it?

Answer 1

the main difference, I think, is that you will have to urgently give birth to a hard raid as soon as your piece of iron dies and you start tearing out your hair everywhere with horror ... because the manufacturer muddied a special algorithm that understands only his hardware! and it's Friday night. and on Monday, some super-important meeting of economists to which you must ensure the uninterrupted receipt of your documentation.

Answer 2

Soft-raid for most non-specific applications.
Modern algorithms + lack of dependence on iron.
As for which raid to do, it depends on the purpose, number, volume of disks, the value of information, and the willingness to invest in reserve volumes. For example, if the disks are large (>=3Tb), RAID-5 and analogs are no longer very good, because in the event of a crash of one disk, there is a chance that the array will not survive until the end of the recovery. Here you need RAID-6, or better RAID-Z2 / 3 or multi-disk mirrors.
If you are really interested in softtrade, you can read about ZFS.
BUT: for a high-quality soft trade, you need a lot of memory, and it is desirable to do all this on server hardware (mother supermicro, xeon, ECC DRAM, etc.). If you wish, you can do it on simpler hardware and with ordinary memory, but this can impose restrictions on reliability, functionality, and speed.
You can read, for example, here .
And yes, don't forget: RAID is not meant for backup. It protects against failure of the disk / disks (if it's not a stripe, of course), but no more. A kirdyk data can occur for a host of other reasons. Therefore, it makes no sense to make a RAID where a backup is needed, as a replacement for it.

Answer 3

Counter question: Software RAID or Hardware RAID - for what?
Depending on the task, maybe no RAID is needed - is an archive copy enough?
Or maybe - SSD will solve the problem much better?

Answer 4

1) With software RAID, the problem is the same - it's just not possible to fish out the desired file. One thing pleases - the software array does not need specific hardware.
2) Gives a load. Tangibility/scary depends on tasks.
3) You can. Depends on tasks.
Vindavozny server from the software raid does not seem to be loaded.

Answer 5

Better hardware raid on a separate controller with memory and battery.
1) it depends on the type of raid
2) some of the processor time and system resources will be spent on maintaining the operation of the software raid
3) in principle, it’s possible, no, it’s not worth it - because it is difficult to predict the reliability of such a complex configuration.

Answer 6

1) No question, simple statement of fact.
2) a dozen does not create a load
3) it’s possible, it’s worth

Answer 7

RAID is needed on a server on which very critical and resource-intensive tasks will be performed.
At the moment, a couple of servers are running on Software RAID 1 and another couple based on Hardware RAID 10.
In the event of a RAID controller failure or a complete server failure, we will start a second machine that is a mirror copy of the first one that failed. The software used on the server is itself responsible for data synchronization. We only have to use the handles to transfer the second machine from SLAVE to MASTER mode.
The task is to get rid of downtime (failure) of the server of the entire server if one disk fails. 5 days a week the server must work non-stop. Starting the second server in MASTER mode requires manual intervention and some time. On Saturday-Sunday, you can safely replace the server or disk.
Now we are choosing a new server and are a little stuck with the choice of RAID.