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> Why do you want a single raid0 over 2 raid1 (Raid10) instead of one |
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> raid1 over 2 raid0 (Raid01)? Greater survivability. |
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> |
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> Here is the potential setups: |
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> |
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> Raid01: |
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> md0 (raid0): sda1 sdb1 |
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> md1 (raid0): sdc1 sdd1 |
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> md2 (raid1): md0 md1 |
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> |
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> Raid10: |
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> md0 (raid1): sda1 sdb1 |
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> md1 (raid1): sdc1 sdd1 |
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> md2 (raid0): md0 md1 |
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> |
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> If sda1 fails: |
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> raid01: md0 also fails (sdb now has garbage data), so md2 relies on |
| 18 |
> md1 for all data. If sdc or sdd fail, md1 will fail and all data is lost. |
| 19 |
> raid10: md0 keeps going by relying on sdb. If sdc or sdd fail md1 |
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> will still function and thus md2 will continue to function. |
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> |
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> With 2 disks failing there are 6 possible combinations (ab, ac, ad, bc, |
| 23 |
> bd, cd). With raid01 there is only a 33% chance of avoiding data loss |
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> (ab, cd). With raid10 there is 67% chance of avoiding data loss (ac, |
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> ad, bc, bd). |
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|
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Thx very much. It's really clear. |
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But I was thinking about performance. I thought that was a performance |
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concern, instead it is about reliability. |
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|
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And what about performance? There are differencies between raid01 |
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and raid10? |
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|
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Thx again and regards, |
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|
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Andrea |
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