Mirrored Network: Local DNS resolution does not work

[peterjuras]

Windows Version

Microsoft Windows [Version 10.0.22621.3155]

WSL Version

2.0.14.0

Are you using WSL 1 or WSL 2?

• WSL 2
• WSL 1

Kernel Version

5.15.133.1

Distro Version

Ubuntu 22.04

Other Software

No response

Repro Steps

1. Update networkingMode to NAT in .wslconfig
2. Run wsl --shutdown
3. Start a WSL2 shell (Ubuntu in my case)
4. Ping a local machine on the network with its DNS name (rutzberry in my case)
5. Ping works, resolved local IP address ✅
6. Update networkingMode to mirrored in .wslconfig
7. Run wsl --shutdown
8. Start a WSL2 shell (Ubuntu in my case)
9. Ping a local machine on the network with its DNS name (rutzberry in my case)

Expected Behavior

Ping does not work anymore and outputs the error ping: rutzberry: Name or service not known

Note: Pinging the actual local IP address does work.

Actual Behavior

Ping should work, just as with networkingMode=NAT.

Diagnostic Logs

https://1drv.ms/u/s!AsTaR5LHyZP9tMJB_nJZr7sGE7XfSA?e=wsNDrt

[byjrack]

I am in the same boat where some flows seem to work in "mirrored", but DNS seems to fail by default. I also enabled dnsTunneling and no change.

Scenarios tested w "mirrored"

• host example.com -> 127.0.0.1:53 connection refused
• host example.com 1.2.3.4 -> resolves via known good DNS
• ping 1.2.3.4 -> ICMP seems to be fine
• curl https://9.8.7.6 -> works fine bypassing dns

I did do a netsh trace and no DNS packets when using the 127.0.0.1 proxy were captured, but ones with the known good server were fine. I checked firewall logs and not seeing any DROPs. Any recommendations on debugging if one of our other network controls might be stepping on this specific proxying feature?

[DaWei-GeGe]

I'm in the same situation.
wsl and windows , cannot access applications through 127.0.0.1,Only through Windows ip

[D9RS]

Same issue for me. Guys, maybe you found some solution?

[chanpreetdhanjal]

Hi. Can you please collect networking logs by following the instructions below?
https://github.com/microsoft/WSL/blob/master/CONTRIBUTING.md#collect-wsl-logs-for-networking-issues

[peterjuras]

@chanpreetdhanjal From a different perspective: Is there any user that has working local DNS with mirrored network mode?