Verification Speed of Data is very Slow

[mamelas]

Dear All,

Usually Backup Write speed varies from 900MB to 1200MB per minute.

Unfortunately Verification of data varies from 100MB to 190MB.

These days during Verification of the data some informational messages appeared with the following message:

The following event was reported on 12/12/2011 7:29:43 PM:

The driver detected a controller error on \Device\Scsi\cpqcissm1.

This error signifies controller errors. These errors are generally caused by hardware that is not functioning correctly. To resolve these errors, try the following actions:

- Slow the SCSI bus.

- Verify that the latest SCSI drivers and firmware are loaded.

If these errors continue to occur, contact the hardware manufacturer.

I have an external tape device, Tandberg Data LTO-3, connected to a SCSI Controller.

Could someone help me to solve the slow verification speed and the above informational message?

Thanks in advance!

[pkh]

In the Windows Device Manager, check that the library is listed as a Unknown Medium Changer with a Microsoft driver.  If it has a Tandberg driver, change the driver using the procedures below

How to uninstall the Original Equipment Manufacturer driver for the medium changer in a robotic libr...

How to uninstall the Original Equipment Manufacturer driver for the medium changer in a robotic libr...

[RahulG]

 The driver detected a controller error on \Device\Scsi\cpqcissm1 correspnds to event id 11 :

Generic trouble shooting would be to check cabling/ Firmware updates for SCSI card / re swapp of the dev ice ( Shutdwon/ Swap out and re-swap in ) ---

refer the following document as well

http://www.symantec.com/business/support/index?page=content&id=TECH5027

Furher if similar events occur get Hardware vendor to look in same...

[teiva-boy]

SCSI is an interesting beast, and in many cases, issues can be tracked down to SCSI ID conflicts, bad terminators or lack of, or bad cabling.  While things may appear to be "working," sometimes bad cables/terminators can cause slowdowns like this.

This is why SAS is the way to go on standalone tape units.  Faster, and easier to deal with.

While at it, upgrade the firmware and drivers for everything available from the SCSI card, drive, library, etc.  

[mamelas]

Thank you all for your responds!

I have unistalled the previous driver but under availiable drivers Unknown Medium Changer  is not listed.

So I used the Microsoft default LTO driver and I re-installed the device from Backup Exec selecting to install drivers from the Backup Exec.

Now I am running a test job in order to check verification speed.

The strange thing in that case is that write speed is very good 1,2gb/minute but the verification speed is only 180mb/minute.

So if it is a communication problem write speed should be also slow! Or I am wrong?

[RahulG]

It is  not neccessary the write sppee will be slow .

[mamelas]

I have made an IO test using Tandberg's Diagnostic Tool...

I am attaching you the results..Any recommendation?

[mamelas]

Please can anybody help me solving this?

[RahulG]

I would suggest you to get in touch with the hardware vendor, Once you have tried the steps from the following document

http://www.symantec.com/business/support/index?page=content&id=TECH5027

[mamelas]

Dear RahulG,

I tried to install Symantec drivers using the wizard.

Pressing the details button I saw that there is no Symantec driver under the specified field and that the program will not change existing driver.

After completing the wizard and booting my computer under tape's drive details the Driver Provider is Microsoft.

I have a Tandberg LTO-3 HH SCSI Tape Device and the link point to Symantec’s driver compatibility is obsolete.

So is it compatible or not? If not do you recommend me to keep Microsoft’s driver or to replace it with Tandberg's original drivers?

[RahulG]

The tape drive should use Symantec tape Drivers and the medium changer should use Microsoft drivers..

Perform the following steps

1. Uninstall the drivers for the tape drive

2. Reboot the server.

3. Download the latest symantec drivers and install it

4. shut down the Ev server and the tape drive

5. Power on the tape drive first

6. once the tape drive is iniallized then power on the server

7. verify the the tape drive is now using the Symantec drivers.

[mamelas]

Dear RahulG,

Thank you for your Guidance.

Do you have any link to download  the drivers?

[VJware]

Either run LiveUpdate or download from here - http://www.symantec.com/docs/TECH158750

[samueljn]

Hi,

Check this article: http://www.symantec.com/docs/TECH39020

[teiva-boy]

It would appear that even Tandberg's OWN diagnostic tests, validates the speeds you are getting.

Have you called Tandberg to confirm?  This could very well be something they could assist with.

[mamelas]

@RahulG

Dear Rahul,

I followed yours above instructions in order to reinstall the driver but nothing changed.

I used live update and installed the latest hotfix regarding device driver intaller.
Unfortunately windows are using Tandberg’s device drivers and still Backup Exec cannot find any available driver for my device (through BE device Installer Wizard)

So is there any compatible driver for my device under Backup Exec? (Current driver for backup exec is td_ltohh.sys)

[mamelas · Accepted solution]

Look like my problem is solved.

Tandberg Tape Drive was the only device connected to the SCSI Controller.

At the back side of the Tape drive were two ports.

One “IN” port and one “OUT” port.

The Tape Drive was firstly connected to OUT port.

I have changed the port to IN and now the average speed has raised to 3.400MB/min.