SOLVED UFS RAID 6 expandable after creation?

[Tim Slaa]

Hello,

Soon i'll be reinstalling my freenas box, upgrading it to the 9.3 beta.
After almost half a year i now know a lot better how to work with freenas and what i require from the box.

Currently running a single ZFS stripe pool for storage. (yes yes i know its not safe, i have all the important stuff backed up dont worry)
But in the last few months i have been reading on the terrible things that can happen if you combine ZFS with non ECC ram, which is what i am currently using.
since the motherboard doesn't support ECC ram and i don't really need the extra functions zfs adds.
i am planning on running ufs in raid 6 starting with 4 x 1TB drives (2TB usable space) which is just enough for now but my storage needs are growing pretty fast.

So here comes the question: Is UFS raid 6 expandable?
(growing by adding drives & growing by replacing drives with bigger ones.)

If this isn't possible what would you recommend me to do?
i am on a very limited budget at this moment and would like to slowly upgrade to 6 x 3TB drives.

Kind regards,

A amature freenas user in need of some advice.

(also sorry for any bad grammar and/or misplaced dots and comma's, I'm dyslectic and English isn't my native language)

 

[anodos]

No UFS in 9.3

 

[Tim Slaa]

this for real? damm that would make freenas a bad choice for me since i don't have ecc memory.

 

[gpsguy]

Yes!

this for real?

 

[Tim Slaa]

i suppose i wont be upgrading to 9.3 then..... damm that sucks. was really looking forward to the update functionality.

Main question remains the same tho, is ufs raid 6 expandable after creation( adding disks + increasing disk size)

 

[anodos]

i suppose i wont be upgrading to 9.3 then..... damm that sucks. was really looking forward to the update functionality.

Main question remains the same tho, is ufs raid 6 expandable after creation( adding disks + increasing disk size)

I'm not an expert on raid, but I think what you want is not possible under softraid. Sticking with old unsupported versions of freenas isn't a great idea either.

Generally, softraid / fakeraid sucks. As far as I'm concerned for data storage you have two options that are pretty good (1) get a proper motherboard with ECC ram and use zfs (2) use a different OS, get a proper raid card with BBU, and use a traditional fs. Both options cost money.

 

[Tim Slaa]

well, money is kinda the issue at the moment. so i will probably upgrade to 9.3 anyway then and pray my ram stays error free for a few years. probably run a memtest every month or so.

- - - off UFS raid topic - - -​

As for raidz2 expansion then, as far as i have read up on it you can only expand those by increasing the size of each drive. and you cant add drives to the actual raid since this would be added as a new vdev (if i remember correctly) which would make the entire array fail if that drive fails.

since i currently have 1 x 2TB, 2 x 1TB and a 250GB (250GB i will not be using) and planning on getting a cheap refurbished 1TB drive to trow along those, and i have room to store 6 3.5" hdd's is it possible to make 2 temporary virtual drives so i dont have to recreate the entire pool (and loose all the data) when i am ready to add the 2 other drives? i have seen this pop up but didn't really look into it much.
(no need to search for me but if you know it of the top of your head it would spare me a few hours browsing the web)

 

[anodos]

well, money is kinda the issue at the moment. so i will probably upgrade to 9.3 anyway then and pray my ram stays error free for a few years. probably run a memtest every month or so.

substitute 'pray' with 'keep good backups'. Which is what you should be doing anyway.

The storage gods do not look favorably on carelessness, and will mercilessly smite your data for your hubris when you least expect it.

 

[Tim Slaa]

substitute 'pray' with 'keep good backups'. Which is what you should be doing anyway.

well if zfs would corrupt the data due to bad memory, wouldnt that be ported over to the backup aswell?

probably gonna save up some money and buy a server motherboard asap, my main rig is in need of a replacement motherboard anyway. gonna look pretty stupid, a Mitx board in a Full-Atx chassis.

 

[DJ9]

Any file system will corrupt the files if the memory is bad. Some just notify you sooner. (if at all)

 

[solarisguy]

Any file system will corrupt the files if the memory is bad. Some just notify you sooner. (if at all)

We talking about a different scenario here. ZFS would happily scramble (=wipe out) all your data during a scrub while a specific undetected memory fault is present. There is no other protection but ECC RAM.

This is not a corruption in a filesystem, as known from the other filesystems...

P.S. Some people try avoiding a scrub. That protects against the total wipeout, but can cause localized*/widespread* damages. (*Which ones? That depends on usage patterns.)

 

[cyberjock]

well if zfs would corrupt the data due to bad memory, wouldnt that be ported over to the backup aswell?

Yep, just like the ECC RAM sticky explains thoroughly. Basically you go ZFS and you should go ECC or not use ZFS (and therefore FreeNAS).

 

[Tim Slaa]

ZFS needs ECC ram, thats quite clear now.

Does anyone know the answer to the question of the topic so i can mark it as solved?
(wont be of any help to me since i will upgrade to 9.3, but maybe for someone else still running freenas 9.2)

 

[cyberjock]

I looked through the manual and I see nothing about expanding UFS. I can't say I'm surprised and I wouldn't expect someone with first-hand knowledge to answer because the number of people who have used UFS in the past can probably be counted on my fingers and toes.