Upgrading from 2 Drive Mirror

[Mikeygsxr750]

Hello All,

I currently have a 2 - 4TB mirror that I am upgrading to 4 - 4TB drives. I wanted input on the best way to move forward with the raid configuration. I haven't yet filled the first Mirrored pool (Movies/TV Shows), but as far as I can tell, the best way to upgrade is to create another, 2 Disk Mirrored Raid, rather than reconfigure all disks to a Raid 10, and reload the data after.

All suggestions and pointers are welcomed, and thank you in advance!

 

[winnielinnie]

You're bringing non-ZFS terms and methods into ZFS.

You can simply add a new mirror vdev with your extra two 4TB drives.

Now your pool will be comprised of two mirror vdevs (2 x 4TB and 2 x 4TB).

ZFS will auto-spread the new writes as you use your pool.

 

[Mikeygsxr750]

Thank you for your speedy reply. Just realized this thread should have been posted into Upgrades. My bad!

That honestly works for me... Simple and easy enough to keep expanding. Researching more on migration of the pool also...

I have been debating on upgrading many things at once, a motherboard and CPU upgrade, while adding this new vdev and pool.

I'm currently using an Optiplex 990 with an i7-2600, 16GB (ddr3) ram VERSUS the upgrade to, a B450m with a 3200G and 16GB (ddr4) ram.

I am not sure the upgrade would make much difference other than the lower power usage. Any input?

 

[sretalla]

I am not sure the upgrade would make much difference other than the lower power usage. Any input?

You're probably right. It will be hard to put your finger on a specific thing that will go faster by enough that you notice.

 

[Mikeygsxr750]

For my use case, serving media, I can't really see a good benefit for the upgrade.

I'll be using the 2nd Mirrored vdev to back up game installation files. Not to be used like Scsi, but just a pool with the setup files.

 

[winnielinnie]

I'll be using the 2nd Mirrored vdev to back up game installation files.

Then you'll have to create a new pool, using that vdev.

Because if you add an additional mirror vdev to your existing pool, you won't have any control of where files are saved, in regards to physical drives.

 

[Mikeygsxr750]

I'll definitely do that. I don't want to keep the media files, with the other files, because of compression ratios. I know video doesn't compress, but the other files should.

I like mirroring, but it makes it a pain to expand. I must buy 2 drives for the storage of one, but I understand all the work being put into storing the data, and would rather not lose it.

 

[winnielinnie]

I'll be using the 2nd Mirrored vdev to back up game installation files. Not to be used like Scsi, but just a pool with the setup files.

I'll definitely do that. I don't want to keep the media files, with the other files, because of compression ratios. I know video doesn't compress, but the other files should.

I like mirroring, but it makes it a pain to expand. I must buy 2 drives for the storage of one, but I understand all the work being put into storing the data, and would rather not lose it.

I think there might be some confusion with ZFS terminology and use. When you say something like "I'll be using the second mirror vdev", it sounds like you're confusing datasets (filesystems) with physical media.

Pools ae comprised of vdevs. Vdevs are comprised of (hopefully) redundant drive configurations (mirror, RAIDZ1, RAIDZ2, etc). All vdevs (and hence all drives) in a pool are treated as a "single unit" in terms of usable storage. (In other words, you can't outright say "I want these faster drives to have this data, and these slower drives to store this other data.")

However, a pool can have an indefinite number of "datasets" (which are essentially their own distinct filesystems.) You can specify different properties for each dataset: encryption, compression, recordsize, snapshots, etc.

Reading your latest reply, it sounds like you will benefit from adding an additional mirror vdev to your existing pool (and hence expanding its storage capacity). In this pool, you create separate datasets based on what type of data they will be writing/reading.

Where a separate pool comes into play is when you're dealing with different storage media. (All SSD, all NVMe, all HDD, etc.) You might build a small, fast pool with vdevs made up of only SSDs. To later add another additional mirror vdev to this pool using a couple HDDs will ruin your plans. (Since you have no control of what gets read from or written to the SSDs or HDDs that comprise this pool)

I think anyone new to TrueNAS or ZFS benefits greatly from this:

ZFS 101—Understanding ZFS storage and performance

Learn to get the most out of your ZFS filesystem in our new series on storage fundamentals.

arstechnica.com

 

[Mikeygsxr750]

I'm definitely not an experienced user when it comes to Zfs. I had learned just enough to begin my first Truenas box, setup Snapshots, and begin filling.

I've learned to upgrade my boot pool, and used an SSD for that, setup my Groups/ Users ACLs, and create an SMB Share. That's where my knowledge stops though.

I'll definitely read your shared information, and thank you for it!!!

The TrueNAS/zfs/BSD community is awesome!