[SOLVED] Can I expand my pool? ZFS expand question?

[nrap]

Hello,

I'm new to the ZFS and nas4free. I have an HP microserver with 2 HDDs 1.5TB WD Green.
I have created a virtual disk with those two hdds, and afterwards a zpool like this:

nas4free:~# zpool status FirstPool
pool: FirstPool
state: ONLINE
scan: none requested
config:

NAME STATE READ WRITE CKSUM
FirstPool ONLINE 0 0 0
raidz1-0 ONLINE 0 0 0
ada0 ONLINE 0 0 0
ada1 ONLINE 0 0 0

errors: No known data errors

Now I've bought another hdd 2TB WD, HOW can I put the hard drive to the FirstPool in order to create a 3 drive zfs pool??
As far as I have read I think I should destroy the pool (probably copy all the files to another drive) recreate the Virtual device with all 3 devices and recreate the pool (???))
Isn't there another way?
Thanks
Nick.

[rocket]

as far as I know, there isn't any other way.

[raulfg3]

You can grow pools whithout losing data in two ways ,

1 change all disk in the pool, one by one doing a resilver in each change, when resilver last disk, your pool grow to new size.
2 create a new pool and add to the existing one.

Eg case 2: You have a Raidz1 of 3 disk, each disk of 1 TB = 2TB free, If you add 3 new disk of 1 TB, to create a new pool, and add this new pool to the existing one, You have a new pool of 4 TB. (1 pool = 2 vdev, 1 vdev = 3 disk)

[rocket]

2 create a new pool and add to the existing one.

Eg case 2: You have a Raidz1 of 3 disk, each disk of 1 TB = 2TB free, If you add 3 new disk of 1 TB, to create a new pool, and add this new pool to the existing one, You have a new pool of 4 TB. (1 pool = 2 vdev, 1 vdev = 3 disk)

Ooh, I didn't know this, nice loophole!

[cancerman]

ZFS supports ORE, Online RAID Expansion, as stated above. Replace each disk with a larger one until all are replaced and the RAID grows.

It doesn't support RLM, RAID Level Migration. Taking a 3 drive RAID, adding a drive and turning it into a 4 drive RAID, while online.

[oleost]

It doesn't support RLM, RAID Level Migration. Taking a 3 drive RAID, adding a drive and turning it into a 4 drive RAID, while online.

You write "While online", does it support to do so if you take the raid offline ?

[Onichan]

It doesn't support RLM, RAID Level Migration. Taking a 3 drive RAID, adding a drive and turning it into a 4 drive RAID, while online.

You write "While online", does it support to do so if you take the raid offline ?

No it doesn't.

[...alex]

I'm sure this question has been answered many times but i couldn't find anything when searching!

Currently, i have 3x2TB disks setup with RADIZ1.

I am starting to run out of space so i would like to add some more disks.

Can i simply purchase identicle disks and expand the Pool?

[raulfg3]

are you try to find expand pool in search bar?:
viewtopic.php?f=66&t=823&p=2442&hilit=expand+pool#p2442

[...alex]

I did read that thread, but obviously not well enough >_<

I guess i will need to buy all new disks! Even if i replace each disk with a larger one, i will only ever be able to have a 3 disk array, right?

[raulfg3]

No you can add a new vded , so you can have your actual 3 Disk plus new ones eg: 3x2TB+3x2Tb = 8TB usable

[anicesteak]

If I recall, the way to do it is replace your 2TB disks with 3TB one disk at a time, waiting for things to sync up in between. Then you can add another disk.

[...alex]

If I recall, the way to do it is replace your 2TB disks with 3TB one disk at a time, waiting for things to sync up in between. Then you can add another disk.

And then add another disk? So you mean... if i have an array with 3 disks, i replace all three with larger disks, i can add a 4th disk to the array? If that's the case, why could i not just add another disk to the array as it stands now?

[raulfg3]

if i have an array with 3 disks, i replace all three with larger disks, i can add a 4th disk to the array?

NO.

Add a 4th disk do ont work

[raulfg3]

PD: have a look at this post:
viewtopic.php?f=66&t=1528

In latest version of Nas4Free autoexpand=on is on by default, but revise it.

[...alex]

Ok, got it. So i have three options:
1) Replace all three disks with bigger disks e.g. 3TB. My array will only ever be able to have 3 disks.
2) Create a new VDev with new disks (this requires an extra disk for redundancy).
3) Copy the data to a temp location, create a new pool with more disks and then copy the data back.

Personally, i think option 3 is the best.

What's the best way to plan for future expansion?

[raulfg3]

I can say my future plan.
I actually have a poll of 5 disk in raidz1 = 5x2TB = 8TB free more or less , in fact 7,15TB real size).
My plan is to expand my pool adding 5 new disk in raidZ1 = 5x2TB = 8TB plus actual 8TB = 16 TB = 14TB real

PD: To do , I need a new SATA controller because motherboard only have 6 SATA Port, but my case support 18 disk.

[...alex]

Cool!

Your way means that you have two disks dedicated to redundancy, whereas if you had it in one giant raidz1 array you would only need 1 disk for redundancy.

[raulfg3]

whereas if you had it in one giant raidz1 array you would only need 1 disk for redundancy

YES, but is not recomended, because fails increase with the number of disk, and because of this is not recomended to have more that 9 disk in a raidz1 ( you can have 90 disk in raidz1 but is recomended that you use 10 pools of 9 disk in raidz1 each one) = 10 disk lost in parity , but more robutness.

[...alex]

It's all very clear now. Thanks for all of your help!

[ChriZathens]

PD: To do , I need a new SATA controller because motherboard only have 6 SATA Port, but my case support 18 disk.

Sorry for the off topic but what case do you have that supports 18 disks?

[raulfg3]

sharkoon rebel 12

rebel12_b_value.jpg

rebel12_b_2.jpg

[ChriZathens]

Nice!
I guess you use 5,25" to 3,5" hdd cages, then??

[raulfg3]

yes

[degen]

Moin,
expanding storage if you don't use stripe setup is always a pain.
I would just replace the drives by bigger ones, but as we know drives a damn expensive these day's.
A while back I decide to reorganize my drives to have the possibility for cheap expansion of storage.

I have two arrays/pools
1) heaven, which is a just a simple stripe (here 2x2TB==4TB usable)
2) hell, which is usually a mirror out of two drives (here 2x1TB = 1TB usable). I have this spare disks from my last heaven upgrade

Heaven dont need redundancy cause it completly backed up once a month.
Hell, contain all new files.

Once a month I copy my files from hell to heaven, then I recreate my full backup, test the backup and delete the files on hell.

If I need more space I add a disk to heaven and sometimes I need a new drive for backup too (depends on compression etc.)
The benefit I have is that I dont need two identical new drives at the same time. My money dictate me which drives I can buy.
Yes, you need double space since every file is mirrored (hell) or on the backup. But this is OK, since I can easy expand storage and always have a REAL backup.

degen