Can't decide on best vdev config

[Ikukuru]

Hi,

I have been using a raidz2 pool with 10 x 2TB disks for a few years. This week I had a double disk failure and rather than risking resilver of two disks, I'm going to rebuild the pool and upgrade along the way, as I have been in need of more storage for a year or more.

I currently have 5x 2TB and 5x 3TB disks and I'm trying to figure out my best configuration going forward. The most I can afford to spend is for another 5x 3TB.

I can't afford to make all raid1 mirror vdev scored the capacity I need with 50% efficiency, so I will stick with raidz2.

10x 3TB raidz2 = 24TB

Is that a really bad idea? Data is mostly photos and other documents that need to be accessible, but are mostly idle.

Thanks for any input

[Brendon]

No its not that bad!

Its basically a compromise between resilver time, performance, expandability, space utilisation. There are plenty of docs on internet discussing this.

- Brendon

[RobRehnmark]

Personally, I would be a little bit nervous to have 10 drives in a pool and only 2 simultaneous drive failures possible.
Is Raidz3 advisable?
(I use Raidz2 with 6 drives.)

[Brendon]

Personally I'm not all that interested in advising people how to deploy storage. I think it's all far too nuanced and subjective for there to be one correct answer. Up to the user to choose their design based on their own constraints etc. In terms of the number of disks vs raidz2/3 I'd say "don't care" he should have backups anyway if it all turns to custard.

I mean seriously there would be a large body of users that would say don't be a miser, use mirrors, and there is merit in that argument too.

For myself I doubt I would go with that many disks, because of power consumption, but thats me.

Cheers
Brendon

[RobRehnmark]

Hence the "Personally, ..."

For me it would also be a bit impractical with so many disks due to heat production if it's in a computer where I want to use the cooling for a powerful CPU without adding too much noise.
But in a server tucked away somewhere it would probably not be an issue.
However, that is also a highly personal decision based on use case and preferences.

[Brendon]

Yep, agree.