How to disconnect a network card in virtual environment?

NTDEV
1

Hi,

I am developing Windows PV network driver and having WHQL test on it
now. When i test NDISTest 6.5(manual), i hit a problem.

One step in NDISTest 6.5 (manual) ask the user to disconnect the Network
Adapter in 60 seconds. It is easy to realize it in a physical system and
unplugging the network cable from network card interface is OK. But in
the virtual machine, it is difficult to emulate this situation. I can
use some command to stop data flow on the network card, but windows can
not reflect this correctly, and the connection of this network card in
Windows virtual machine is still OK.

Is it necessary that the network driver do some process to tell windows
that the connection is down?
Any other suggestion?

Thanks
Annie.

2

This test checks that the driver behaves well when
the cable is disconnected (sends the media disconnect indication,
completes unsent packets, etc.) and when the cable is connected back.
Knowing this, you can do whatever is needed to please the ndistest.

(I wonder if XEN counts as a supported system for HCT or DTM ?)

–pa

ANNIE LI wrote:

Hi,

I am developing Windows PV network driver and having WHQL test on it
now. When i test NDISTest 6.5(manual), i hit a problem.

One step in NDISTest 6.5 (manual) ask the user to disconnect the Network
Adapter in 60 seconds. It is easy to realize it in a physical system and
unplugging the network cable from network card interface is OK. But in
the virtual machine, it is difficult to emulate this situation. I can
use some command to stop data flow on the network card, but windows can
not reflect this correctly, and the connection of this network card in
Windows virtual machine is still OK.

Is it necessary that the network driver do some process to tell windows
that the connection is down?
Any other suggestion?

Thanks
Annie.

3

Does your PV network driver have some notion of Media Connect State? Does
it reflect some sort of ‘connected to virtual switch’ state?

If not then you can try:

  1. Not reporting that you support Media Connect and asking for a waiver from
    WHQL.

  2. Reflecting the PV ‘connected to virtual switch’ state as media state and
    then use some mechanism at the PV layer to connect/disconnect the virtual
    device to the virtual switch.

  3. Simulate media connect in your miniport driver and add a custom WMI
    method or variable mapped to an OID to ‘connect’ and ‘disconnect’ the
    adapter so you can manually trigger the appropriate response.

  4. Some other solution - there are probably lots.

Good Luck,
Dave Cattley
Consulting Engineer
Systems Software Development

“ANNIE LI” wrote in message news:xxxxx@ntdev…
> Hi,
>
> I am developing Windows PV network driver and having WHQL test on it now.
> When i test NDISTest 6.5(manual), i hit a problem.
>
> One step in NDISTest 6.5 (manual) ask the user to disconnect the Network
> Adapter in 60 seconds. It is easy to realize it in a physical system and
> unplugging the network cable from network card interface is OK. But in the
> virtual machine, it is difficult to emulate this situation. I can use some
> command to stop data flow on the network card, but windows can not
> reflect this correctly, and the connection of this network card in Windows
> virtual machine is still OK.
>
> Is it necessary that the network driver do some process to tell windows
> that the connection is down?
> Any other suggestion?
>
> Thanks
> Annie.
>

4

However if the characteristics flags are set to indicate a virtual miniport
shouldn’t DTM skip this test? Maybe you should try using a Cisco VPN client
as it is one I use some of the time for work. If it fails then maybe an
email to the DTM group would be appropriate.

“Pavel A.” wrote in message news:xxxxx@ntdev…
> This test checks that the driver behaves well when
> the cable is disconnected (sends the media disconnect indication,
> completes unsent packets, etc.) and when the cable is connected back.
> Knowing this, you can do whatever is needed to please the ndistest.
>
> (I wonder if XEN counts as a supported system for HCT or DTM ?)
>
> --pa
>
>
> ANNIE LI wrote:
>> Hi,
>>
>> I am developing Windows PV network driver and having WHQL test on it now.
>> When i test NDISTest 6.5(manual), i hit a problem.
>>
>> One step in NDISTest 6.5 (manual) ask the user to disconnect the Network
>> Adapter in 60 seconds. It is easy to realize it in a physical system and
>> unplugging the network cable from network card interface is OK. But in
>> the virtual machine, it is difficult to emulate this situation. I can use
>> some command to stop data flow on the network card, but windows can not
>> reflect this correctly, and the connection of this network card in
>> Windows virtual machine is still OK.
>>
>> Is it necessary that the network driver do some process to tell windows
>> that the connection is down?
>> Any other suggestion?
>>
>> Thanks
>> Annie.
>>
>

5

So if you are in control over front end and backend of the pv driver it
would seem to be easy enough to provide a test interface driven from the
backend to simulate a media disconnect. That would avoid the whole ‘go beg
whql for dispensation’ thing, which would seem to me to be more work and
certainly more aggravation than just doing enough to pass this test.
Mark Roddy

On Sun, Feb 15, 2009 at 10:55 AM, ANNIE LI wrote:

> Hi,
>
> I am developing Windows PV network driver and having WHQL test on it now.
> When i test NDISTest 6.5(manual), i hit a problem.
>
> One step in NDISTest 6.5 (manual) ask the user to disconnect the Network
> Adapter in 60 seconds. It is easy to realize it in a physical system and
> unplugging the network cable from network card interface is OK. But in the
> virtual machine, it is difficult to emulate this situation. I can use some
> command to stop data flow on the network card, but windows can not reflect
> this correctly, and the connection of this network card in Windows virtual
> machine is still OK.
>
> Is it necessary that the network driver do some process to tell windows
> that the connection is down?
> Any other suggestion?
>
> Thanks
> Annie.
>
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6

Hi ,

Thank you guys very much.
Base on your suggestion, i have an idea to realize this disconnection.
please point out if there are some faults in my idea.

I plan to add a control in the backend. When user want to disconnect the
virtual network card, the pv driver will be notified, and then this
driver will send notification to top layer driver on it. I searched the
help document and find using NdisMIndicateStatus function can realize
this feature.

Need pv network driver do more process( such as: fail sending and
receiving packets.) except for using NdisMIndicateStatus to notify
protocol drivers?

Thanks
Annie.