zvol or dataset

[hellomynameisleo]

I am currently using a dataset on my truenas connected over SMB to a single pc. I found out about using zvols to create a iscsi instead to mount directly to windows and it would give better performance.

If checksum errors was to be detected on the zvol would trueNas know what files has been corrupted? I ask this because truenas will see the zvol as a virtual drive as a whole and not see the individual files like it would do on a dataset and this matters because I'm running trueNAS on stripped vdevs and would prefer to replace the corrupted files from a backup.

Also is there a way to allocate 100% space to a zvol when creating one? I only see an option for inputting the amount of gb/tb manually.

 

[Patrick M. Hausen]

I am currently using a dataset on my truenas connected over SMB to a single pc. I found out about using zvols to create a iscsi instead to mount directly to windows and it would give better performance.

I doubt that claim, because SMB has way more agressive client side cacheing plus asynchronous writes, which block storage doesn't.
But you can of course give it a try.

If checksum errors was to be detected on the zvol would trueNas know what files has been corrupted?

No. To TrueNAS it's just some arbitrary bytes.

I ask this because truenas will see the zvol as a virtual drive as a whole and not see the individual files like it would do on a dataset and this matters because I'm running trueNAS on stripped vdevs and would prefer to replace the corrupted files from a backup.

Recipe for desaster.

Also is there a way to allocate 100% space to a zvol when creating one? I only see an option for inputting the amount of gb/tb manually.

You should never fill your zpool to more than 70-80 percent with even lower numbers when using the pool for block storage, i.e. iSCSI.

Here's all you need to know about block storage in TrueNAS:

Resource - The path to success for block storage

ZFS does two different things very well. One is storage of large sequentially-written files, such as archives, logs, or data files, where the file does not have the middle bits modified after creation. This is optimal for RAIDZ. It's what most...

www.truenas.com

 

[hellomynameisleo]

I doubt that claim, because SMB has way more agressive client side cacheing plus asynchronous writes, which block storage doesn't.
But you can of course give it a try.


No. To TrueNAS it's just some arbitrary bytes.


Recipe for desaster.


You should never fill your zpool to more than 70-80 percent with even lower numbers when using the pool for block storage, i.e. iSCSI.

Here's all you need to know about block storage in TrueNAS:

Resource - The path to success for block storage

ZFS does two different things very well. One is storage of large sequentially-written files, such as archives, logs, or data files, where the file does not have the middle bits modified after creation. This is optimal for RAIDZ. It's what most...

www.truenas.com

Would windows tell me the file has caused an error if truenas can't detect the file that has corrupted?

I understand about the 80% usage but I have a dataset that already allocated 100% of the space automatically without warning, it would be the same as allocating 100% zvol of the available space in the pool.

 

[WI_Hedgehog]

Depending on the usage iSCSI is a proper solution, but not for file sharing--use a file sharing protocol for all the reasons @Patrick M. Hausen states.

If you're worried about corruption run a RAID-Z2 setup like most members here and avoid that issue from the outset. If you have mission-critical data add an extra drive for RAID-Z3.

TrueNAS is Datacenter-Level software; you want to run "the best stuff" for good reason, though that means backing your setup with good hardware. Gaming system hardware and mindset is excellent for gaming systems, and the same rational goes for Small Business servers. However, if you're stepping into top-end Enterprise systems the hardware has to handle the different type of workload--it's like a gaming system is tweaked like mad for speed, unlike a word processing and spreadsheet office desktop; the same mentality goes here, configure a screamer of a setup if you want, but make it reliable and fast in the ways a NAS needs to be fast. (Example: There's no need for high-end graphics cards when many of us don't even hook up monitors. Save the money, invest it wisely.)

 

[Patrick M. Hausen]

Would windows tell me the file has caused an error if truenas can't detect the file that has corrupted?

I understand about the 80% usage but I have a dataset that already allocated 100% of the space automatically without warning, it would be the same as allocating 100% zvol of the available space in the pool.

I don't know if and how Windows reports damaged files. And if that is really a striped pool, loss of one disk will not only lose some files. The entire pool will be toast.

And second, if you fill a pool to 100%, it will stop working. Up to a point that you cannot even delete files to make some room and will have to destroy the pool.

Please start reading on how ZFS works.

ZFS Primer

Background information about the Zettabyte File System (ZFS).

www.truenas.com