Dockertools: network nat is ambigous

[nphmuller]

When I create a new ASP.NET Web Application in VS 15.6.4 with Docker Support enabled, I immediately get the following build error:

1>WebApplication3 -> c:\users\mulle\source\repos\WebApplication3\WebApplication3\bin\WebApplication3.dll
1>docker-compose  -f "c:\users\mulle\source\repos\WebApplication3\docker-compose.yml" -f "c:\users\mulle\source\repos\WebApplication3\docker-compose.override.yml" -f "c:\users\mulle\source\repos\WebApplication3\obj\Docker\docker-compose.vs.debug.g.yml" -p dockercompose8443036482498000778 --no-ansi up -d --build --force-recreate --remove-orphans
1>2 matches found based on name: network nat is ambiguous
1>C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\MSBuild\Sdks\Microsoft.Docker.Sdk\build\Microsoft.VisualStudio.Docker.Compose.targets(363,5): error : 2 matches found based on name: network nat is ambiguous.
1>C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\MSBuild\Sdks\Microsoft.Docker.Sdk\build\Microsoft.VisualStudio.Docker.Compose.targets(363,5): error : 
1>C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\MSBuild\Sdks\Microsoft.Docker.Sdk\build\Microsoft.VisualStudio.Docker.Compose.targets(363,5): error : For more troubleshooting information, go to http://aka.ms/DockerToolsTroubleshooting
1>Done building project "docker-compose.dcproj" -- FAILED.

docker network ls produces the following output:

NETWORK ID          NAME                DRIVER              SCOPE
5c2f84200f27        nat                 nat                 local
90484bbaf01b        nat                 nat                 local
33131c23180b        none                null                local 

Both nat network cannot be removed because:

> docker network rm 5c2f84200f27
Error response from daemon: nat is a pre-defined network and cannot be removed 

According to https://github.com/moby/moby/issues/20648#issuecomment-188215208 duplicate network names in Docker are by design. So this might be a bug.

[nphmuller]

Docker factory reset can be used as a workaround.
Factory reset still creates 2 nat driver networks for me, but with a unique name:
```

docker network ls
NETWORK ID NAME DRIVER SCOPE
c16d631fff32 3a58d72283c3b3da9debb8bb753d0327b1e15437dcb293e46bc1340b87a52290 nat local
fe93466d138c nat nat local
70d7f97915be none null local
````

[bospoort]

The factory reset didn't work for me. I uninstalled Docker and then reinstalled. There were still two networks named nat. After uninstall, I had to remove all folders named Docker or .docker from Program Files, ProgramData, my profile etc. Then reinstall, and I had only one network named nat. Uninstalling Docker seems to leave a lot behind.
I'm also not sure if two nat networks is by design.

[TribeDataWorksJim]

I have tried factory reset, reinstalling (and tried to find all occurrences of the folders), but am still having this issue.

[dbreshears]

You might try this network cleanup script. It has helped with similar issues in the past -> https://github.com/MicrosoftDocs/Virtualization-Documentation/tree/master/windows-server-container-tools/CleanupContainerHostNetworking

.\WindowsContainerNetworking-LoggingAndCleanupAide.ps1 -Cleanup

[bplasmeijer]

same here on (Version 18.05.0-ce-rc1-win63 (17439))
docker run --rm --platform linux busybox echo hello --network d9e5b31562b8
docker.exe: Error response from daemon: network nat is ambiguous (2 matches found on name).
docker network ls
NETWORK ID NAME DRIVER SCOPE
d9e5b31562b8 nat nat local
029ff73b534f nat nat local
8b14c3c19549 none null local

• reinstall and prune network didn't work for me
• clean up script doesn't work; still two nat's

[andrehe001]

same for me with docker version 18.05.0-ce-rc1-win63 (17439). Any help or fixes in the queue?

[tbertenshaw]

same here with 18.03.1-ce-win65 (17513)

Tried uninstalling and reinstalling docker and Hyper-v and still have two nat's called nat.

[fals]

I have the same problem:

Docker version 18.03.1-ce, build 9ee9f40

NETWORK ID NAME DRIVER SCOPE
0aa6fcfc5fc9 bridge bridge local
225fbdbda06e dockercompose7610429240741085608_default bridge local
1e6fca6d8459 dockercompose7610429240741085608_default bridge local
9784cadbee3a host host local
7cf1551affda none null local
2f20552ffff9 setup_default bridge local

two defaults with the same name

[dnllowe]

Same problem for me on a Windows 10 machine running Windows Containers. Not sure how or why Docker started listing two nat networks, but I was able to fix the problem by:

• Opening Hyper-V Manager
• Shutting down the MobyLinuxVM

After that, everything worked fine. Spent about two days on this. Hope this helps someone else!

[Fredoid]

Same probem with Docker version 18.03.1-ce, build 9ee9f40, Windows 10 and Windows Containers.
docker network ls shows 2 networks nat.

[Fredoid]

I've just found a solution in this topic

Simply run this following ps script to clean keys named "nat" and restart your computer.

$KeyPath = "HKLM:\SYSTEM\CurrentControlSet\Services\vmsmp\parameters\SwitchList"
$keys = get-childitem $KeyPath

foreach($key in $keys) {
    if($key.GetValue("FriendlyName") -eq 'nat') {
        $newKeyPath = $KeyPath+"\"+$key.PSChildName
        Remove-Item -Path $newKeyPath -Recurse
    }
}

remove-netnat -Confirm:$false

Works on Windows 10 Pro with Docker version 18.03.0-ce-win59, build 0520e24302.

Thanks

[TribeDataWorksJim]

I am still having this issue. Those networks are not listed in the registry on my system. Also, in some writeups, they mention a PS command get get a list of networks, that command isn't recognized on my Windows 10 box

[Fredoid]

Hi, Sometimes it is mentioned Get-NetNat PS function, but in my case this function always return a empty result. The script above worked nice twice.

I my case this problem appeared when I unstalled and re-installed Docker. Two times, and same issue on both case.

[dmitriykanarskiy]

Hi, i don't know which of this helped, but i've got rid of duplicate 'nat' networks as follows:

1. Stop service docker
2. Unregister service docker
3. Stop service HNS
4. Delete all instances of registry keys with the name of 'nat' network
5. Delete "C:\ProgramData\Microsoft\Windows\HNS\HNS.data"
6. Delete "C:\ProgramData\docker\network\files\local-kv.db"
7. Restart computer

Hope this will help.

[TribeDataWorksJim]

That finally fixed my issue. I believe it was step 5 or 6 that done it! Thanks!!!

[SeriousM]

at finally fixed my issue. I believe it was step 5 or 6 that done it! Thanks!!!

Same here! My steps were

1. Stop service docker
2. Stop service HNS
3. Delete "C:\ProgramData\Microsoft\WindowsHNSHNS.data"
4. Delete "C:\ProgramData\docker\network\files\local-kv.db"
5. Start service HNS
6. Start docker

no pc restart required.

[kpabich]

at finally fixed my issue. I believe it was step 5 or 6 that done it! Thanks!!!

Same here! My steps were

1. Stop service docker
2. Stop service HNS
3. Delete "C:\ProgramData\Microsoft\WindowsHNSHNS.data"
4. Delete "C:\ProgramData\docker\network\files\local-kv.db"
5. Start service HNS
6. Start docker

no pc restart required.

Worked for me!
Thank you.

[pritamhere]

I've just found a solution in this topic

Simply run this following ps script to clean keys named "nat" and restart your computer.

$KeyPath = "HKLM:\SYSTEM\CurrentControlSet\Services\vmsmp\parameters\SwitchList"
$keys = get-childitem $KeyPath

foreach($key in $keys) {
  if($key.GetValue("FriendlyName") -eq 'nat') {
      $newKeyPath = $KeyPath+"\"+$key.PSChildName
      Remove-Item -Path $newKeyPath -Recurse
  }
}

remove-netnat -Confirm:$false

Works on Windows 10 Pro with Docker version 18.03.0-ce-win59, build 0520e24302.

Thanks

tried this and it fixed my issue after restart. running on windows 10.

[philipktlin]

I have the same issue on a testing machine. When running e2e tests, we will uninstall and install docker (moby) and this issue happens randomly. I would like to ask, does anyone know what the root cause is.

[kvskranthikumar]

These steps worked for me on Windows 10 -

Delete "C:\ProgramData\Microsoft\WindowsHNSHNS.data"
Delete "C:\ProgramData\docker\network\files\local-kv.db"

[stiko]

The way I solved this is by listing the networks
docker network ls as @Fredoid mentioned you'll see a duplicated network as the error indicated,
then use the id of the network causing the error to remove it
docker network rm NETWORK_ID

[mail2hjain]

at finally fixed my issue. I believe it was step 5 or 6 that done it! Thanks!!!

Same here! My steps were

1. Stop service docker
2. Stop service HNS
3. Delete "C:\ProgramData\Microsoft\WindowsHNSHNS.data"
4. Delete "C:\ProgramData\docker\network\files\local-kv.db"
5. Start service HNS
6. Start docker

no pc restart required.

Worked for me as well. Thanks.