iSCSI Works For About 30sec Then Drops and Timeouts

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Sep 18, 2017
So I just set up a fresh install of FreeNAS 11.1 on a HP Dl180G6

I followed the instructions for setting up an iSCSI connection to Windows and that seemed to work just fine.

But as I start copying to the iSCSI extent (from a laptop on the network to the server VM) I get good speeds of 80-100MB/s but after around 30 seconds it drops to zero or something really low like 3MB/s.
After about 5 mins after the first drop I get the windows error telling me an "unexpected error is keeping me from copying the file".
Error 0x80070079: The semaphore timeout period has expired.

Does anyone know what might be causing this?
I've looked around and it seems any semaphore related timeout doesn't mention use of iSCSI, or really have any actionable solution.
While my specs may not be the best they should at least work I would think.

Additionally trying to deleted any half copied files inside the server VM on the iSCSI extent takes forever and often just doesn't work unless the VM is restarted.

I am running Windows Server 2016 as a VM on ESXi on the other end of iSCSI
And copying my files from external laptops/desktops, useing MS2016 as the central point of storage
9x2TB WD Red & Black drives in Z2 (9x1x2TB)
2x4TB WD Golds in Mirror
H200 in HBA mode
Xeon L5640 (CPU use has never gone above 10%)
20GB of ram (probs not enough for maximum performance, but it should work. FreeNAS flat-lines at ~15GB in use)
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