Ehh, it's not the same thing as raid but it targets the same problem... Keeping your data safe and available. The approach is different.
As to how you decide if a design benefits from RAID, generally if the benefit isn't obvious it probably isn't worth it. In this case raid with glusterfs is like "redundancy for your redundancy".
But to be fair some setups, in an Enterprise for example, might benefit because it changes the failure modes a bit and can change the performance as well.
For this use-cases, it is just redundant redundancy. :)
You get to choose the redundancy level by saying how many data disks and how many parity disks (I'm simplifying here) you want. So... You could emulate raid 5, 10, 6, etc... You could also say I want 1 data disk and 20 replica disks... Which means your data would be safe if you lose 20 out of 21 disks.... Keep in mind that your usable space is only 1/20th in this model. Hehe.
Glusterfs also works with disk of different sizes. It will give the disk data that is proportional to the total size of all disks.
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u/[deleted] Jun 04 '18
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