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Freenas on USB stick. Which file system?
- Thread starter Caliber
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Oh, I never realized that. (I installed Freenas to try it out a few times, but never checked the file system). Guess that's one less thing to worry about.
I have a vague recollection about reading that article a few years ago. I may need to reconsider it, but right now I feel it's worth the risk with raid-z to avoid losing 2/5 drives for parity.
I have a vague recollection about reading that article a few years ago. I may need to reconsider it, but right now I feel it's worth the risk with raid-z to avoid losing 2/5 drives for parity.
I do appreciate the warning, and the 90% figure does seem reasonable.
If you don't mind going off track for a minute; do you know how the percentage of raid-z/raid-5 systems that end up with an unrecoverable pool (over a reasonable period, say max 10 years)?
If it's 1% for raid-z/raid-5 compared to 0.1% for raid-z2/raid6, then that's a reasonable risk for me. If it's 20% compared to 2%, then that's a bit scary.
I'm asking since I'm currently running a system with 2 internal drives and 3 external USB drives (the idea is to replace the external USB drives with the 5x3gb raid in Freenas, which is why I'm reluctant to go with raid-z2 since my storage capacity will barely be increased from what I have now) and I've only had a single drive failure so far. The idea of two of them happening in a quick succession seems very foreign, but maybe I've just been lucky thus far.
If you don't mind going off track for a minute; do you know how the percentage of raid-z/raid-5 systems that end up with an unrecoverable pool (over a reasonable period, say max 10 years)?
If it's 1% for raid-z/raid-5 compared to 0.1% for raid-z2/raid6, then that's a reasonable risk for me. If it's 20% compared to 2%, then that's a bit scary.
I'm asking since I'm currently running a system with 2 internal drives and 3 external USB drives (the idea is to replace the external USB drives with the 5x3gb raid in Freenas, which is why I'm reluctant to go with raid-z2 since my storage capacity will barely be increased from what I have now) and I've only had a single drive failure so far. The idea of two of them happening in a quick succession seems very foreign, but maybe I've just been lucky thus far.
The external drives won't be part of the Raid-Z array. They're just part of my current solution, which I'm looking to get rid of.
The idea is to get rid of the external drives in favor of a Freenas 5x3GB Raid-Z array (and possibly use the external drives for backup).
You aren't understanding that article I linked(or you didn't read it). You really need to go back and read it. The issue isn't with 2 drives failing at the same time. It has to do with unrecoverable error rates for hard drives. The issue is that sectors that were readable in the past are no longer readable and you have no redundancy to protect you. Poof, data lost. I'd really write out a long explanation. But the bottom line is that the article I linked explained it very well. Better than I ever could have.
But long story short, unless you trust the manufacturers that their drives fail less frequently than they claim, if you own a pool with more than 12TB of storage space, you WILL lose data when you have a single disk failure. You literally have a 100% statistical chance of losing data.
But long story short, unless you trust the manufacturers that their drives fail less frequently than they claim, if you own a pool with more than 12TB of storage space, you WILL lose data when you have a single disk failure. You literally have a 100% statistical chance of losing data.
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