Windows System Software -- Consulting, Training, Development -- Unique Expertise, Guaranteed Results

Before Posting...
Please check out the Community Guidelines in the Announcements and Administration Category.

More Info on Driver Writing and Debugging


The free OSR Learning Library has more than 50 articles on a wide variety of topics about writing and debugging device drivers and Minifilters. From introductory level to advanced. All the articles have been recently reviewed and updated, and are written using the clear and definitive style you've come to expect from OSR over the years.


Check out The OSR Learning Library at: https://www.osr.com/osr-learning-library/


Interesting WinDbg Issue

Chris_Rhodes-2Chris_Rhodes-2 Member Posts: 1
Greetings,

I have a strange issue that I?d like feedback on. I was struggling with getting WinDbg to attach to a system via ethernet to do some driver debugging and for days the host would not attach to the target. I have multiple systems in our lab running Windows 10.1607 and no issues with network debugging on any of them except one system. The system in question has a COMExpress module.

I checked all the obvious things:

Firewall disabled.
Ping works between host and target in both directions.
Disabled all other ethernet network ports (system has 4) except the one I?m targeting.
Specified busparams in the dbgsettings for the bus.device.function of the target adapter.
Verified all params to bcdedit are correct.
Correct version of debugging tools
System up-to-date

After failing to get the connection working, I decided to break out Wireshark and collect traces and compare them to a known-good working system. I installed Wireshark on the host and configured my traces simply collecting everything from the target?s IP address. At this point I thought well I should start up WinDbg and viola, target connects to WinDbg and works like a charm. To make sure I wasn?t imaging things, I killed everything, rebooted and started WinDbg and no connection. I went back and forth with this half a dozen times having Wireshark running then not. The target reliably connects to WinDbg when Wireshark is running, but won?t connect without Wireshark running.

Now I?m fairly ignorant about networking, but it would be good to have better understanding of what I?m seeing here. Any thoughts on this would be greatly appreciated.

Thanks,
-Chris.
Sign In or Register to comment.

Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Upcoming OSR Seminars
OSR has suspended in-person seminars due to the Covid-19 outbreak. But, don't miss your training! Attend via the internet instead!
Kernel Debugging 30 Mar 2020 OSR Seminar Space
Developing Minifilters 15 Jun 2020 LIVE ONLINE
Writing WDF Drivers 22 June 2020 LIVE ONLINE
Internals & Software Drivers 28 Sept 2020 Dulles, VA