iSCSI timeout and Win2012 high CPU uitlization

[saupatel]

Hello,

I recently created a iSCSI LUN on my QNAP TES-1885U and connected it to my Win2012 server (ServerA) as X: drive. The QNAP and ServerA have a Mellanox 40Gbps card and they are connected directly. Now, I also have a shared folder on the QNAP, so I mapped to the QNAP share on ServerA (net use Z: \\qnap\share1). Then I created a simple robocopy command to copy file contents from the share (Z:) to my iSCSI LUN (X:). This process goes on fine for some time, and then I start getting errors -

" EventID: 0x10300c8
Description: [iSCSI] Target iqn.2004-04.com.qnap:es-x85u:iscsi.nas01santest.1191b5.0 sid 4000013700010200 cid 1 iSCSI command timed out (op code 0) "

During this time, however ServerA goes in an almost non-operational state. It's almost like the CPU is at 100%, thus making it impossible to login or do anything. I end up doing a hard shutdown and hope that it comes back up without any data loss (as it is a production server). This has now happened twice as I've tested the process of coping the files twice.

Once I can get back into ServerA, I see the following in the EventLogs - "Target did not respond in time for a SCSI request. The CDB is given in the dump data." And there are no other events at all during the time the machine is in a crash like state till I restart it.

Can someone please assist me with this and let me know why this is happening and how to fix this issue? Any comments/suggestions are appreciated.

Thank you,
Sau

[Trexx]

I would first open a helpdesk ticket with QNAP as this is a community support forum.

Are you running QTS or QES firmware on your NAS? Are you on the most current release?

Can you determine roughly where the copy job is crashing? Is it the same place each time? Could it be a corrupted/inaccessible file that isn't being handled cleanly by robocopy?

[storageman]

Yes QES or QTS?
I suspect a network packet/issue.
Is the share and ISCSI connection running on the same NIC(s)?
Can you run the same test on a 1GbE connection?
What happens when you copy from windows server to LUN rather NAS share.