SOLVED iSCSI question about ZVOL

[JoeFlorida]

I have my iSCSI working great but I just used plain files. I figured I would try to do it properly.
I first configured a data set called iSCSI and then I tried to create a ZVOL under that and I called it extent0

mainvol\iSCSI (dataset )
mainvol\iSCSI\extent0 ( 2TB zvol )

when I was creating my extents in iSCSI sharing, I selected DEVICE instead of FILE and it found my zvol.
all was working just fine, I connected with a windows PC, formatted the drive and then tried to use it.
it copied maybe 1G of data then the network speed went to near ZERO.

all I can says is that there was no file created called extent0 so I have no idea where the data went,
the NAS GUI slowed down and was becoming unresponsive until I delete the ZVOL. Once the ZVOL was deleted the GUI snapped back to life.
Is there something I did wrong when creating the ZVOL, I mean, should I have manually created a file for the ZVOL to be connected to?
Am I just using the concept of a zvol wrong?

 

[dlavigne]

Which build version of FreeNAS (from System -> Information)? Also, post your hardware specs.

 

[JoeFlorida]

FreeNAS 9.10.2-U3 (e149f269)
Supermicro X11SSM-F, Xeon E3-1245, 32G crucial ECC ram.
I don't think this was a hardware failure, my current theory is that it should have created a physical file when I created the ZVOL on the storage panel and it did not. I think I was able to play with the drive because it cached the whole volume in 32G of ram and once it has used up the cache space it slowed down and stopped accepting data. If I had created a ZVOL less than 32G I might have never noticed it had not created a file. That is just my theory of course.

 

[JoeFlorida]

I just miss-understood how a zvol works, I couldn't get past the no-file created. I think the issue was when I created the zvol I had forced a 512 block size instead of letting it inherit the block size. Once I created it with the inherit block size everything worked just fine. I can easily max out my network while transferring large files. it no longer slows down or locks up.