Docker login to local server fails with "unknown backend type for cloud login"

[hmottestad]

Description

After upgrading to Docker Desktop community 2.3.0.5 the docker login command fails with unknown backend when provided with a minimal domain name.

Steps to reproduce the issue:

1. docker login localhost:443

Describe the results you received:
unknown backend type for cloud login: localhost:443

Describe the results you expected:
Same as when using (with . at end of domain name): docker login localhost.:443

Additional information you deem important (e.g. issue happens only occasionally):

Should also work for local domains. In our case our docker registry is running on https://docker-registry:443.

Output of docker version:

Client: Docker Engine - Community
 Azure integration  0.1.15
 Version:           19.03.12
 API version:       1.40
 Go version:        go1.13.10
 Git commit:        48a66213fe
 Built:             Mon Jun 22 15:41:33 2020
 OS/Arch:           darwin/amd64
 Experimental:      false

Server: Docker Engine - Community
 Engine:
  Version:          19.03.12
  API version:      1.40 (minimum version 1.12)
  Go version:       go1.13.10
  Git commit:       48a66213fe
  Built:            Mon Jun 22 15:49:27 2020
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          v1.2.13
  GitCommit:        7ad184331fa3e55e52b890ea95e65ba581ae3429
 runc:
  Version:          1.0.0-rc10
  GitCommit:        dc9208a3303feef5b3839f4323d9beb36df0a9dd
 docker-init:
  Version:          0.18.0
  GitCommit:        fec3683

Output of docker info:

Client:
 Debug Mode: false

Server:
 Containers: 5
  Running: 5
  Paused: 0
  Stopped: 0
 Images: 1475
 Server Version: 19.03.12
 Storage Driver: overlay2
  Backing Filesystem: extfs
  Supports d_type: true
  Native Overlay Diff: true
 Logging Driver: json-file
 Cgroup Driver: cgroupfs
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
 Swarm: inactive
 Runtimes: runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 7ad184331fa3e55e52b890ea95e65ba581ae3429
 runc version: dc9208a3303feef5b3839f4323d9beb36df0a9dd
 init version: fec3683
 Security Options:
  seccomp
   Profile: default
 Kernel Version: 4.19.76-linuxkit
 Operating System: Docker Desktop
 OSType: linux
 Architecture: x86_64
 CPUs: 4
 Total Memory: 7.78GiB
 Name: docker-desktop
 ID: 7Q62:UF3G:QNWB:WCGN:SW6X:PQLH:TAE3:PI7I:3MXA:4Y5P:G4W7:3IHT
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 HTTP Proxy: gateway.docker.internal:3128
 HTTPS Proxy: gateway.docker.internal:3129
 Registry: https://index.docker.io/v1/
 Labels:
 Experimental: false
 Insecure Registries:
  docker-registry.eos
  docker-registry:443
  127.0.0.0/8
 Live Restore Enabled: false
 Product License: Community Engine

Additional environment details (AWS, VirtualBox, physical, etc.):

[itkg-ppottie]

when you read help , you can understand why:

 docker login --help
Log in to a Docker registry or cloud backend.
If no registry server is specified, the default is defined by the daemon.

Usage:
  docker login [OPTIONS] [SERVER] [flags]
  docker login [command]

Available Commands:
  azure       Log in to azure

So localhost is interpreted like "command" so like a login into azure . insane indeed
you can define an another host name in your /etc/hosts with dot in name like

127.0.0.1 localhost registry.local

[RedHawker]

It seems like Docker Desktop 2.3.0.5 introduced this bug, reverting to 2.3.0.4 is the current workaround as far as I can tell.

It broke docker login to existing private repositories, which is a regression.

[hmottestad]

It seems like Docker Desktop 2.3.0.5 introduced this bug, reverting to 2.3.0.4 is the current workaround as far as I can tell.

It broke docker login to existing private repositories, which is a regression.

Another workaround is to append your domain name with a dot.

Eg. localhost -> localhost.

[thaJeztah]

Sounds like this may be an issue in the command-line used for cloud integration; does the problem go away if you disable the "enable cloud experience" option in the Docker Desktop preferences (under preferences -> command line);

(actually, it may have moved, so perhaps it's named different, so let me know if you can't find the option)

[justincormack]

Apologies for that we will get a fix out ASAP, please use one of the workarounds above for now.

[thaJeztah]

I moved this ticket to the compose-cli repository, which is where the bug looks to be in 👍

[maartenvanderhoef]

It seems like Docker Desktop 2.3.0.5 introduced this bug, reverting to 2.3.0.4 is the current workaround as far as I can tell.
It broke docker login to existing private repositories, which is a regression.

Another workaround is to append your domain name with a dot.

Eg. localhost -> localhost.

didn't work for me

docker login 127.0.0.1:port did the trick.

[gtardif]

This has been fixed and shipped in Desktop, feel free to re-opened if you encounter this issue with the latest Desktop version (Edge or stable)