Troubleshooting tips for vDash DOE connection

[steely12]

Spent a few evenings troubleshooting why vDash couldn't recognise my connection to a 2021 Polestar2. Initially suspected the cheap DOE cable but dug in and ended up getting trace from Wireshark.
Side question, why does Wireshark and vDash running together just crash. This was a little tedious.

In the end I ruled out the cable and figured that my Tailscale (VPN tunnel) service was swallowing all the DoIP packets.

So the lesson to share is as follows. If you're trying to connect via DOE then do first check you don't have odd VPN stuff going on at all.
The specific tell that gave it away was
'Get-NetRoute -DestinationPrefix "169.254.0.0/16"' from an admin powershell. In error mode this returned multiple entries. Once I'd disabled tailscale it only returned one.

Hope this helps someone save a bit of debugging time.

[T5 T6 Schnappi]

Thanks for sharing this.
My personal recommendation is to use a dedicated computer with as less as possible 3rd party software installed. Especially no 3rd party antivirus, security, firewall and VPN software. As those clearly interfere with the vehicle communication. The lesser useless running background processes, the better.
Using your cluttered everyday machine for stuff like Vdash or VIDA is always a bad idea.
And Vdash most probably has some sort of anti tampering routines. It most likely detects software like Wireshark or the Npcap drivers and crashes on purpose, to prevent reverse engineering of how Vdash works.