Hyper-V and iSCSI through Tape Redirector to tape backup

pdube · Wed Sep 12, 2012 1:51 pm

I am using Data Protection Manager 2012 on a VM, with the tape backup connected on the host (obviously). Both servers are Windows 2008 R2.

I am using Starwind Tape Redirector to have the VM see the tape backup. Microsoft iSCSI is used on the VM.
The connection to the tape backup seems to work (device is shown working properly in Device Manager), but the backup does not work.

I have the following error (using Microsoft Data Protection Manager 2012):

DPM encountered a critical error while performing an I/O operation on the tape Company Data Servers-LT-1Days-Copy0-00000002 (Barcode - ) in Drive Quantum DLT-S4 Tape Drive. (ID 30101 Details: The request could not be performed because of an I/O device error (0x8007045D))

When using DPM directly on the host, the backup works fine without any error.

Any ideas?

Thu Sep 13, 2012 2:32 pm

Hi Paul,
Did you get a chance to check if VM uses the same drivers as the parent host?
It could also happen that a write error on the DPM side sent device offline.
To check this I will need the most recent log file, which can be found in the Tape Redirector installation folder.
Please send the log file to support@starwindsoftware.com

pdube · Thu Sep 13, 2012 6:15 pm

I aldready sent the logs to support 2 days ago and had no news after that.

Sat Sep 15, 2012 9:31 am

Sorry for a bit of mess we did not match you here, on MS forums and via e-mail. Did you use the same e-mail to send from you've used to register on this forum? Please let me know so I could kick the support people a bit.

Sun Sep 16, 2012 6:36 am

OK, your problem is - tape drive does support transfer size of 64KB and not more and MS initiator keeps sending requests up to 192KB in size so they get rejected. What you need - either increase transfer on your tape driver (check vendor-specific settings) on target *OR* truncate MS initiator request size. Please see this thread for more information about your issue, how to fix it and what registry settings should be used:

http://www.starwindsoftware.com/forums/ ... t1089.html

Please give it a try and let know did it work or not

pdube · Mon Sep 17, 2012 3:51 pm

Yes it worked very well by changing the registry setting. Thanks a lot.

Paul

Mon Sep 17, 2012 9:10 pm

Good. Please keep us updated. Also make sure to post your ideas here:

http://www.starwindsoftware.com/forums/ ... t2903.html

Much appreciated!

pdube wrote:Yes it worked very well by changing the registry setting. Thanks a lot.

Paul