WSL 2 mirrored networking breaks NFS mounts (“Connection timed out”) #12508

wpwoodjr · 2025-01-27T19:48:51Z

Windows Version

Microsoft Windows [Version 10.0.26100.2894]

WSL Version

WSL version: 2.3.26.0 Kernel version: 5.15.167.4-1 WSLg version: 1.0.65 MSRDC version: 1.2.5620 Direct3D version: 1.611.1-81528511 DXCore version: 10.0.26100.1-240331-1435.ge-release Windows version: 10.0.26100.2894

Are you using WSL 1 or WSL 2?

WSL 2
WSL 1

Kernel Version

5.15.167.4-microsoft-standard-WSL2

Distro Version

Ubuntu 22.04.5 LTS

Other Software

When using WSL 2 mirrored networking mode, any attempt to mount an NFS share from within WSL 2 fails with errors:

$ sudo mount -v -t nfs ub-nuc:/home/wpwoodjr /home/wpwoodjr/ub-nuc
mount.nfs: timeout set for Mon Jan 27 13:45:44 2025
mount.nfs: trying text-based options 'vers=4.2,addr=192.168.86.200,clientaddr=192.168.86.41'
mount.nfs: mount(2): Invalid argument
mount.nfs: trying text-based options 'vers=4,minorversion=1,addr=192.168.86.200,clientaddr=192.168.86.41'
mount.nfs: mount(2): Connection timed out
mount.nfs: Connection timed out

Key Observations

Mount works from other Linux clients on the same network (e.g., a Raspberry Pi).
Mount works if I revert WSL 2 to the legacy NAT networking mode.
Turning off Windows Firewall does not help.
Pinging or otherwise accessing the NFS server (e.g. rpcinfo -p serverIP) still works, but mount -t nfs … fails.

Request

Fix or provide guidance on how to use mirrored networking with protocols like NFS that may rely on particular port/protocol interactions.
Alternatively, document known limitations of mirrored networking mode for advanced protocols.

Thank you for looking into this issue!

Repro Steps

Enable mirrored networking (set networkingMode=mirrored in .wslconfig).
Install NFS client tools in WSL:

sudo apt-get update
sudo apt-get install nfs-common

Attempt to mount an exported NFS share:

sudo mount -v -t nfs serverIP:/path /mnt/test

The command eventually returns an error:

mount.nfs: mount: Connection timed out

Expected Behavior

The NFS share should mount successfully inside WSL 2, just like it does from a Raspberry Pi or other standard Linux environment on the same LAN.

Actual Behavior

The mount attempt times out.
No traffic is visibly blocked by the Windows Firewall (which I turned off for testing).
Reverting to non-mirrored networking mode in .wslconfig and restarting WSL immediately fixes the issue.
So it appears mirrored networking specifically interferes with NFS.

Diagnostic Logs

From wsl client with mirrored networking:

$ rpcinfo -p
   program vers proto   port  service
    100000    4   tcp    111  portmapper
    100000    3   tcp    111  portmapper
    100000    2   tcp    111  portmapper
    100000    4   udp    111  portmapper
    100000    3   udp    111  portmapper
    100000    2   udp    111  portmapper

$ showmount -e ub-nuc
Export list for ub-nuc:
/home/wpwoodjr 192.168.86.0/24

$ nc -vz ub-nuc 2049
Connection to ub-nuc (192.168.86.200) 2049 port [tcp/nfs] succeeded!

$ sudo mount -v -t nfs ub-nuc:/home/wpwoodjr /home/wpwoodjr/ub-nuc
mount.nfs: timeout set for Mon Jan 27 13:45:44 2025
mount.nfs: trying text-based options 'vers=4.2,addr=192.168.86.200,clientaddr=192.168.86.41'
mount.nfs: mount(2): Invalid argument
mount.nfs: trying text-based options 'vers=4,minorversion=1,addr=192.168.86.200,clientaddr=192.168.86.41'
mount.nfs: mount(2): Connection timed out
mount.nfs: Connection timed out

After disabling mirrored networking:

$ sudo mount -v -t nfs ub-nuc:/home/wpwoodjr /home/wpwoodjr/ub-nuc
mount.nfs: timeout set for Mon Jan 27 14:44:39 2025
mount.nfs: trying text-based options 'vers=4.2,addr=192.168.86.200,clientaddr=172.24.87.14'
mount.nfs: mount(2): Invalid argument
mount.nfs: trying text-based options 'vers=4,minorversion=1,addr=192.168.86.200,clientaddr=172.24.87.14'

$ ls ub-nuc
Desktop    Downloads   Music     Public     Videos      linux-dev    snap             win10.log
Documents  ...

The text was updated successfully, but these errors were encountered:

github-actions · 2025-01-27T19:49:53Z

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View similar issues

Please view the issues below to see if they solve your problem, and if the issue describes your problem please consider closing this one and thumbs upping the other issue to help us prioritize it!

Open similar issues:

With WSL2's Mirror Network Mode, Services on the Windows Host are Inaccessible, but the Reverse is Possible (#12399), similarity score: 0.74

Closed similar issues:

Can't mount NFS from within WSL2 Ubuntu 22.04 (#9790), similarity score: 0.75
NFS cannot be used in WSL (#10331), similarity score: 0.72
WSL 2 can't mount NFS share (#8640), similarity score: 0.72
Networking mirrored can't work on WSL2 (#10632), similarity score: 0.72

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wpwoodjr · 2025-01-27T20:37:07Z

Logs attached

WslLogs-2025-01-27_15-28-25.zip

github-actions · 2025-01-27T20:38:38Z

Diagnostic information

.wslconfig found
Detected appx version: 2.3.26.0

patelmail · 2025-01-31T23:30:07Z

Just want to confirm that I am seeing the same thing after upgrading wsl with bridged mode being deprecated.

NFS is completely broken in wsl2 with mirrored networking, works fine on my other Linux boxes.

Info:

WSL version: 2.3.26.0
Kernel version: 5.15.167.4-1
WSLg version: 1.0.65
MSRDC version: 1.2.5620
Direct3D version: 1.611.1-81528511
DXCore version: 10.0.26100.1-240331-1435.ge-release
Windows version: 10.0.26100.2894

Logs: WslLogs-2025-01-31_18-26-08.zip

Networking Logs: WslNetworkingLogs-2025-01-31_18-28-01.zip

ljcbaby · 2025-02-01T06:17:18Z

same issue

patelmail · 2025-02-08T21:51:09Z

BUMP. Is there any work being done to address this? To deprecate Bridged mode and not have a working replacement (at least not working with NFS as it previously did) in Mirrored mode is a shame.

Pretty much every file I want to access within wsl2 is located on my Unraid NAS so wsl2 is just dead for me until/if someone comes up with a fix for this weird issue.

patelmail · 2025-02-11T21:03:05Z

Is anyone able to get this to work with even NAT networking? Seems like a firewall issue because I can't get it to work with NAT networking either.

sudo mount -v NFS_HOST_IP:/mnt/user/data/media/movies /mnt/nfs/movies

mount.nfs: timeout set for Tue Feb 11 15:57:23 2025
mount.nfs: trying text-based options 'vers=4.2,addr=NFS_HOST_IP,clientaddr=NFS_CLIENT_IP'
mount.nfs: mount(2): Invalid argument
mount.nfs: trying text-based options 'vers=4,minorversion=1,addr=NFS_HOST_IP,clientaddr=NFS_CLIENT_IP'
mount.nfs: mount(2): Operation not permitted
mount.nfs: trying text-based options 'addr=NFS_HOST_IP'
mount.nfs: prog 100003, trying vers=3, prot=6
mount.nfs: trying NFS_HOST_IP prog 100003 vers 3 prot TCP port 2049
mount.nfs: prog 100005, trying vers=3, prot=17
mount.nfs: trying NFS_HOST_IP prog 100005 vers 3 prot UDP port 42220
mount.nfs: mount(2): Permission denied
mount.nfs: Operation not permitted

Does this have something to do with Hyper-V firewall? Bridged mode this was working fine but with NAT or mirrored I am unable to get NFS mounts to work. Sigh.

Edit: I was able to get nfs mounts to work using "insecure" option on the NFS host with NAT networking (I'm assuming this works for mirrored as well). Bridged didn't require this since there was no port translation.

So we're back to square one of broken NFS on WSL2 with mirrored networking (where there should be no port translation going on).

github-actions bot added the needs-author-feedback label Jan 27, 2025

microsoft-github-policy-service bot removed the needs-author-feedback label Jan 27, 2025

OneBlue added the needs-attention label Jan 28, 2025

patelmail mentioned this issue Feb 8, 2025

How to Use NFS in WSL2 with mirror mode ? #11442

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WSL 2 mirrored networking breaks NFS mounts (“Connection timed out”) #12508

WSL 2 mirrored networking breaks NFS mounts (“Connection timed out”) #12508

wpwoodjr commented Jan 27, 2025

github-actions bot commented Jan 27, 2025

wpwoodjr commented Jan 27, 2025

github-actions bot commented Jan 27, 2025

patelmail commented Jan 31, 2025

ljcbaby commented Feb 1, 2025

patelmail commented Feb 8, 2025

patelmail commented Feb 11, 2025 •

edited

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WSL 2 mirrored networking breaks NFS mounts (“Connection timed out”) #12508

WSL 2 mirrored networking breaks NFS mounts (“Connection timed out”) #12508

Comments

wpwoodjr commented Jan 27, 2025

Windows Version

WSL Version

Are you using WSL 1 or WSL 2?

Kernel Version

Distro Version

Other Software

Repro Steps

Expected Behavior

Actual Behavior

Diagnostic Logs

github-actions bot commented Jan 27, 2025

Logs are required for review from WSL team

View similar issues

Open similar issues:

Closed similar issues:

wpwoodjr commented Jan 27, 2025

github-actions bot commented Jan 27, 2025

patelmail commented Jan 31, 2025

ljcbaby commented Feb 1, 2025

patelmail commented Feb 8, 2025

patelmail commented Feb 11, 2025 • edited Loading

patelmail commented Feb 11, 2025 •

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