Can't connect to localhost using host.docker.internal

Actual Behavior

Trying to connect to azure mssql within docker container. Bitvise client is running on windows host, bound to all interfaces (0.0.0.0) on port 1435. Trying to access it using tsql with host parameter host.docker.internal port 1435 but times out after +/- 2 minutes, bitvise logs show no communication attempts. If i try to connect directly to the database IP address the connection is established but access is denied as per server access rules (IP address not allowed to connect).

Steps to Reproduce

Install Rancher Desktop, updated to 1.2.1.

Built container with net=host or net=bridge or not setting it at all

Run:

• tsql -H host.docker.internal -p 1435 -U [user] -P [password] -D [database]
• tsql -H host.rancher-desktop.internal -p 1435 -U [user] -P [password] -D [database]
• tsql -H host.rancher-desktop.internal -p 1435 -U [user] -P [password] -D [database]
• tsql -H 127.0.1.1 -p 1435 -U [user] -P [password] -D [database]

WSL2 is used

Result

tsql times out or refuses to connect.

Expected Behavior

Login to the database server and query databases

Additional Information

Routing info inside Rancher Desktop host

Rancher Desktop Version

1.2.1

Rancher Desktop K8s Version

1.22.7

Which container runtime are you using?

moby (docker cli)

What operating system are you using?

Windows

Operating System / Build Version

Windows 10 Enterprise, build 19044

What CPU architecture are you using?

x64

Linux only: what package format did you use to install Rancher Desktop?

No response

Windows User Only

Custom defined VPN

[gunamata]

@Nino-K , we already have an FAQ item for this. https://docs.rancherdesktop.io/faq#q-can-containers-reach-back-to-host-services-via-hostdockerinternal

[jandubois]

disabling that rule has me able to connect from RD to the host again

@dougbreaux Thanks for confirming that this was a local config issue. The new firewall rule proposed by @Nino-K seems to fix the problem for everyone who has responded so far.

I’m going to hide your earlier messages as “outdated” to prevent confusing users who find this issue via a Google search.

BTW, I find that sometimes when I stop and start a container, the host.docker.internal hostname is gone from hosts.

Please file a separate issue for unrelated problems!

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I’ll leave this bug open for now until we have figured out if we want to add the firewall rule to the installer or some other way to make it easier for users to enable it.