First Build

[ipsum]

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[ipsum]

Just as an FYI, AnandTech reviewed the HDD I am going to use for my build: http://anandtech.com/show/8794/hgst-deskstar-nas-6-tb-review.

 

[travanx]

Seems confusing in the comments on who owns HGST. All of my Hitachi drives have failed over the years, Deskstar implies the ticking of death to me. Western Digital was the only manufacturer that didn't have 100% failures on me. That is what lead me to freenas and WD Red drives. Please keep us updated on how the HGST do in your setup. I would love 5x6TB!!!

 

[ipsum]

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[ipsum]

I put everything together and am now trying to figure out the best drive configuration. I would like to go with 8*6TB in Raid-Z3.

- It seems that 'officially' I should go with either 7 or 11 disks when using Z3
- 11 is out of the question, as I do not have that much space in my case; more importantly (I most likely could hack something together), it would be too much to handle for my 32GB of RAM
- 7 seems... not enough. I'd rather have 30TB of space (especially considering that it is recommended to not use over 80% of available storage space)

So, my question: Is it really such a bad idea to go with 8 drives in Raid-Z3? Would I even notice the (potential) decrease in performance on a 1GbE link---I am assuming the only time I would is during a scrub?

Any pointers? Thanks! :)

 

[Ericloewe]

I put everything together and am now trying to figure out the best drive configuration. I would like to go with 8*6TB in Raid-Z3.

- It seems that 'officially' I should go with either 7 or 11 disks when using Z3
- 11 is out of the question, as I do not have that much space in my case; more importantly (I most likely could hack something together), it would be too much to handle for my 32GB of RAM
- 7 seems... not enough. I'd rather have 30TB of space (especially considering that it is recommended to not use over 80% of available storage space)

So, my question: Is it really such a bad idea to go with 8 drives in Raid-Z3? Would I even notice the (potential) decrease in performance on a 1GbE link---I am assuming the only time I would is during a scrub?

Any pointers? Thanks! :)

Don't worry about adhering to the RAM rule of thumb too strictly. It's just a rule of thumb and it's intentionally vague.

If you'll be using compression, there may be no impact going from 7 to 8 drives. For home use, it never was that much of a problem in the first place.

 

[ipsum]

Thanks for the reply; 8 drives it is, then.

Seems like it might be a good idea to set up a 7 drive Raid-Z3 in the beginning for the sake of comparing performance.

Just out of interest: what would be the ideal configuration for 8 drives? Raid-Z2? I've read somewhere Mirror 4x2?

 

[Ericloewe]

Thanks for the reply; 8 drives it is, then.

Seems like it might be a good idea to set up a 7 drive Raid-Z3 in the beginning for the sake of comparing performance.

Just out of interest: what would be the ideal configuration for 8 drives? Raid-Z2? I've read somewhere Mirror 4x2?

RAIDZ2 wouldn't be ideal either, but it would work.

 

[ipsum]

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[cyberjock]

8 drives is okay for RAIDZ2. I've helped friends do 8-disk vdevs of RAIDZ2. With 8 disks I'd absolutely do RAIDZ2. Z3 if you want to be extra paranoid. ;)

 

[ipsum]

8 drives is okay for RAIDZ2. I've helped friends do 8-disk vdevs of RAIDZ2. With 8 disks I'd absolutely do RAIDZ2. Z3 if you want to be extra paranoid. ;)

I am borderline OK with 8 disks in Raid-Z2 now, but I am more worried about what will happen when I upgrade all drives to 8TB a few years down the line. I'd rather do Z3 in that case... Unless it would severely impact performance for whatever reason.

Thanks!

 

[ZakMckracken]

I've got 10x6TB with 32GB of RAM and I've had some behaviors that are indicative of an ARC that is too small. As a result I wouldn't recommend 6x6TB with 16GB of RAM. It might work, and it might work "okay". But I wouldn't go that route unless you are ready to drop money on upgrading to 32GB of RAM if it becomes necessary.

Not meaning to hijack the thread, but I've seen you comment about having 32GB of RAM for your 10x6TB in a couple of places, and how it's a limiting factor. At what point do you think 32GB RAM becomes a limitation (as people here in the forums have said the 1GB/1TB is a general guideline rather than a hard rule)? Do you think it would also be a limiting factor in a 10x4TB?

 

[ipsum]

Not meaning to hijack the thread, but I've seen you comment about having 32GB of RAM for your 10x6TB in a couple of places, and how it's a limiting factor. At what point do you think 32GB RAM becomes a limitation (as people here in the forums have said the 1GB/1TB is a general guideline rather than a hard rule)? Do you think it would also be a limiting factor in a 10x4TB?

Depends on what you end up doing with your build and what kind of features you would like (i.e. deduplication).

10x4TB in (I am assuming) Raid-Z2 is 32TB (technically about 29TB) of usable space, which should be completely fine in a normal use/home user scenario.

 

[ZakMckracken]

Thanks ipsum. Yes, I'm planning Raid Z2 (after the mistake of making my current box Z1 and non-ECC). I've lucked out with this first box and not had any major issues, but I'm starting to get some checksum errors on a couple of the 5 drives, am at 79% capacity, and want to build a new (proper) server.