lu_disk_lbwrite errors when copying large files

[rcase13]

I have FreeNAS-8.0.2-RELEASE-amd64 (8288) running on a Workstation 8 virtual machine. I have created a 50GB ZFS volume and am using it as a datastore for an ESX 5.0 cluster. I am presenting the volume to ESX using iSCSI. When I try to copy a large vmdk file to the datastore it copies fine for about 2GBs of the 31GB vmdk file then starts spewing out the following errors:

Nov 14 04:38:37 freenas_prod istgt[1681]: istgt_lu_disk.c:3960:istgt_lu_disk_lbwrite: ***ERROR***lu_disk_write() failed
Nov 14 04:38:37 freenas_prod istgt[1681]: istgt_lu_disk.c:6051:istgt_lu_disk_execute: ***ERROR***lu_disk_write() failed

Smaller files less than 2GB work just fine. What could cause FreeNAS to fail on large files?

 

[laser47]

I've had the same problem, and it's spewing all the time now causing my VMWare ESXi 4.1 server to lock up. I was copying a large vmdk file (1TB) from one datastore to another when I received the first error. Smaller files of 30-60 GB copied fine. I do have an error in the message log when I boot FreeNAS that the partition doesn't begin or end on a track boundary. I've seen in another thread that this is just a warning because ZFS doesn't understand VMware's vmfs format.

I've got 4 x 2TB drives in raidz2, and created 3 x 1TB ZVOL devices extents that I've added to my iSCSI initiator. In VMware, I've combined these into a single datastore. VMware can't talk to a LUN 2TB or larger, so I've split them out like this. The file that I was copying probably crossed the boundary into the second LUN.

I saw some suggestions to disable CHAP, and to scrub the volume. I've disabled CHAP without any change, and the scrub is still running with the ESX server off. :(


* Are there any advanced settings either in FreeNAS or VMware that I should check? I've used defaults for them both. I've had the VMware connected to a Linux iSCSI target and LVM for a year or so with these settings.
* Does it matter that I used ZFS Volumes intead of creating a file extent? Are there any advantages / disadvantages to setting it up one way or the other?
* Should I worry about the Geometry error about not beginning or ending on a track boundary?
* Any other suggestions or places to look?