Questions from a user moving from windows storage spaces

[pomtom44]

Hi all
I currently run a windows storage spaces server as my NAS, but want to try get away from windows and use something which is "proper"
Alot of people have pointed me to truenas / freenas so im checking it out

What im having a hard time understanding and finding info on is different disks
In my windows machine, I have a large mix of different disks (budget build so I get what I can get) and storage spaces just lets me put any old disk in and add it to the pool
And when a disk fails, i just get a new larger one and replace it with that, so slowly adding more space to my pools

Reading up about truenas online, i have a mix of info about what you can and can't do with disks and matching

Am I able to add any disk I want to the pool, or do they have to be matching
Also when changing out a disk, can I replace a disk with a larger one to get more storage in the pool? or does it have to be matching as well?


my second question is around the share side of things
in storage spaces, you create a virtual drive, and it just uses the entire disk pool (or you can split it up if you want)
So say I have 10tb of disk storage, I can allocate 5tb to one virtual disk, 2 to another and 3 to the last, and it will just spread over all the physical hard drives as it needs to

Is there a way to do something similar in truenas, or do I have to have a share per pool of disks?

Also, is it possible to have both iscsi mapping and NFS/SMB to the same share?
I have a few different applications which access my current shares in different ways so want to make sure I can keep that going


And finally, expanding storage via a direct attach storage SAN
I have my eyes on a decent sized san in a local auction site
Can I add this as a drive pool to truenas?
(Does it support iscsi storage as pool storage)

Thanks in advance, and sorry if the answers are easily found, just having a hard time finding what I need

 

[sretalla]

but want to try ...[to]... use something which is "proper"

I have a large mix of different disks (budget build so I get what I can get) and storage spaces just lets me put any old disk in and add it to the pool

You'll need to think about this if you want to use ZFS... those 2 things aren't really compatible.

Am I able to add any disk I want to the pool, or do they have to be matching

Depends on the pool type.

For a striped pool (no redundancy), you can do that. Any single disk failure renders the entire pool unrecoverable, so you probably don't want to do that (unless you enjoy losing your data).

For a pool of mirrored VDEVs, you can add additional mirrors (2 disks at a time) and retain single drive failure protection.

For RAIDZ VDEVs (pools containing one or more of those), you can't currently add individual disks... search the forum for RAIDZ expansion and you'll see that it's coming, but we don't really know when.

For mirrors and RAIDZ, you will only get the equivalent of the smallest member disk from all disks unless or until you change all disks to be the same (larger) size (autoexpand will sort that out when the time is right).

Also when changing out a disk, can I replace a disk with a larger one to get more storage in the pool? or does it have to be matching as well?

As above, doesn't have to match, but you will only get the matching size from it until all disks are the same larger size.

my second question is around the share side of things
in storage spaces, you create a virtual drive, and it just uses the entire disk pool (or you can split it up if you want)
So say I have 10tb of disk storage, I can allocate 5tb to one virtual disk, 2 to another and 3 to the last, and it will just spread over all the physical hard drives as it needs to

Is there a way to do something similar in truenas, or do I have to have a share per pool of disks?

Depending on the use for that, you're talking about a dataset or a ZVOL in ZFS language. Yes, those concepts exist and work as you describe (although you don't have to allocate unless you specifically want to limit one or all of the datasets/ZVOLs).

Also, is it possible to have both iscsi mapping and NFS/SMB to the same share?
I have a few different applications which access my current shares in different ways so want to make sure I can keep that going

Possible but not advised... maybe referring to the point above, you can share one dataset with SMB, another with NFS and a zvol with iSCSI from the same pool and that's perfectly acceptable.

And finally, expanding storage via a direct attach storage SAN
I have my eyes on a decent sized san in a local auction site
Can I add this as a drive pool to truenas?
(Does it support iscsi storage as pool storage)

That's really only an enterprise feature, but some folks have done it with CORE... it kind-of defeats the point as TrueNAS would be your SAN in the first place. Adding direct attached storage in an external SAS enclosure is the best option (disk shelf products are probably cheaper to get second hand anyway).

 

[pomtom44]

Thanks for the useful info post

Iv done some more reading and watched a few youtube videos and got my head around pools and vdev
My understanding is I can use the same disks in a vdev, and then link them together in the pool, so long as I have enough redundancy in the vdev
EG 4x 2tb and 6x 4tb drives in 2vdevs, then combine them into a single pool

Then share that pool back out into network shares

So as long as I build my vdevs using teh same size disk I should be ok?
(Which might mean selling a few smaller drives and getting a more consistant spread

for the sharing question, the reason I do this is I have different services mapping the drives differently
EG I have a home file share, which is run via nextcloud using SMB sharing, but for backups my backup server accesses the share via iscsi
So same data on the file server, but different ways of accessing it

I guess for both of these questions I can just make a temporary server on a VM and just try for myself, see what happens

And the final question was wrong, my fault for getting confused while writing it
It was a DAS not SAN, so does truenas support that in a easy to use way?

 

[sretalla]

So as long as I build my vdevs using teh same size disk I should be ok?

If all disks are the same size in a VDEV, you get the most possible capacity from all disks. VDEVs don't have to be the same width (number of member disks) in the same pool, but maintaining the same RAIDZ level and width for all VDEVs is recommended. (which would make a 4x2TB and 6x4TB mix not so great (although technically can be done and will work... just don't expect consistent performance and potentially losing half of the 4x2TB to RAIDZ2 parity).

I have a home file share, which is run via nextcloud using SMB sharing, but for backups my backup server accesses the share via iscsi
So same data on the file server, but different ways of accessing it

I think you're mixing pool and share in those words...

You can place a ZVOL on your pool (usually named "tank" in examples in the forum) and share that via iSCSI.

Then you may create a dataset on tank (called homeshares) and share that via SMB.

Both forms of sharing on the same pool, but not sharing the same content.

It was a DAS not SAN, so does truenas support that in a easy to use way?

Search for the keyword "enclosure" in the forums.

There are (as I said) examples of folks using FiberChannel enclosures, but those aren't supported on the free product, so I would stay well away from that.

External SAS enclosures (sometimes called disk shelves) are a much better (and commonly used) way to go.

Make sure you think about how your disks will be attached... either with an onboard SATA controller or via an HBA... most certainly not via any kind of RAID controller (unless it can be flashed into IT mode and stop acting as a RAID controller).

What's all the noise about HBA's, and why can't I use a RAID controller?

This is relevant to FreeNAS and TrueNAS CORE. Some parts of it might also be relevant to Scale, but I don't really know how reliable the Linux drivers are. 1) An HBA is a Host Bus Adapter. This is a controller that allows SAS and SATA devices to be attached to, and communicate directly with...

www.truenas.com

Also, since you didn't mention that part of hardware, make sure you use an Intel NIC (or Chelsio if you're going 10Gbit). Make sure you do your research on the model and driver support or you're in for a world of difficulty and troubleshooting.

 

[danb35]

Also, is it possible to have both iscsi mapping and NFS/SMB to the same share?

To clarify: It's possible, but not recommended, to have two or more of NFS, SMB, and/or AFP protocols sharing the same dataset/directory. It is not possible to combine that--i.e., share that same dataset/directory--with iSCSI. iSCSI presents a shared block device--you'd connect to it from a client machine, which would then treat it like a disk, format it to whatever filesystem is desired, etc. SMB/NFS/AFP provide shared file storage; iSCSI provides shared block storage. Both the file share, and the iSCSI extent, can be on the same pool, but they can't be the same portion of that pool.