RAID0 to RAID10

[strudel]

Hi guys,

I'm pretty new to FreeNAS, especially when it comes to hardware.

I've been runninga FreeNAS server for some years, but now I want to add drives to allow for redundancy.

My setup is 2x Seagate 4TB hard drive in RAID0. I recently bought 2 WD Gold (awesome deal on Amazon...) 4TB each and I would like to add them as a backup to my first pool (8GB stripe). So basically, I would like to turn my RAID0 setup into RAID10.

Is it possible to do this without losing my data (I have a full backup however) or do I need to wipe everything and start from scratch?

If it's not possible, I would only want to swap the old drives with the new ones, can this easily be done (I see a replace disk option in the GUI)?

Thanks for your support!

 

[Basil Hendroff]

In the ZFS space, RAID10 is equivalent to RAIDZ2. I suspect you're going to have to rebuild. You will find this guide useful in understanding what your ZFS options are https://forums.freenas.org/index.ph...ning-vdev-zpool-zil-and-l2arc-for-noobs.7775/

Edit: Oops! I meant RAID6.

 

[garm]

Please stop using raid analogies.. ZFS RAIDZ2 is not equivalent to conventional RAID10...

If you have a striped pool you can attach new drives to the existing vdevs consisting on single drives, making it a pool of mirror vdevs.

I’m not sure if you can use the UI however, and I don’t have the time to do the reading at the moment

 

[Basil Hendroff]

@garm My bad. The information I provided was wrong anyway.
@strudel This post might be useful https://www.ixsystems.com/community...-disks-with-2-striped-and-then-mirrored.7956/

 

[strudel]

Thanks guys, I'm pondering the option to just replace the old drives with the new ones. I just got an error (DEGRADED) so I think one of my disk is failing...

Is the procedure to replace disks in a stripe the same as the one described here in section 9.5.2 (https://www.ixsystems.com/documentation/freenas/11.2/storage.html)? I would have to put the drive in, click "Replace drive" in the GUI, wait for it to resilver and repeat for the 2nd drive, right?

 

[garm]

Ya, but if it’s already starting to degrade you should proabobly not do that.. build a new pool and copy off the content instead.. you are about to loose your original pool

 

[strudel]

Ok, is it safe to copy from the « degrading » pool or should I copy from backup?

 

[garm]

What is the output of zpool status -v?

 

[strudel]

See attached snips from the shell. After the last one, there's a series of files (with errors I guess). Should I delete those?

 

[garm]

I would not do any writing to the pool, just set up the new pool and rsync or ZFS send the content of your broken pool.

 

[strudel]

Thanks for the reply. Are there tutorials that could help me perform this? I have no idea how to do this.

 

[JaimieV]

Nearby thread: https://www.ixsystems.com/community/threads/howto-migrate-data-from-one-pool-to-a-bigger-pool.40519/

 

[sretalla]

I often see people confused about the difference between RAID0+1 and RAID10 and even calling them the same thing.

A stripe of mirrors and a mirror of stripes are not the same thing.

ZFS can do a stripe of mirrors (2 or more mirrored VDEVs in a single pool), but can't do a mirror of stripes... there's no way to mirror VDEVs together within the same pool (you can do a stripe of stripes though if you really hate keeping your data, but want that to go really fast on it's way to binary heaven).

You can clearly do an x-way mirror (but that's a single VDEV).

You could use snapshots and localhost replication to get some kind of similar result (with a bit of time lag), but performance and OS treatment of that setup is nowhere near the same as RAID0+1