Docker ssh:// wont' work, stderr=zsh:1: command not found: docker

[ankanch]

I have the same problem, whereby I try to execute docker command from windows 10 to Docker on OS X 10.

as below:

kanch@LAPTOP-KANCH:~$ docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS           NAMES
kanch@LAPTOP-KANCH:~$ docker -H tcp://192.168.1.104:2375 ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS             NAMES
kanch@LAPTOP-KANCH:~$  docker -H ssh://platform@192.168.1.104 ps
error during connect: Get http://docker/v1.40/containers/json: command [ssh -l platform 192.168.1.104 -- docker system dial-stdio] has exited with exit status 127, please make sure the URL is valid, and Docker 18.09 or later is installed on the remote host: stderr=zsh:1: command not found: docker

tcp:// just won't works as the reason is command docker not found.

I found in issues it is possible related to the shell I use, then I tried powershell, cmd, bash, git bash. NONE of them works.

is there any fix for this?

[AkihiroSuda]

On the remote host, PATH needs to be set.

[JustDevZero]

Hmmm... I'm sorry for reopening, but this is somehow untrue, unless @ankanch had done anything that I missed:

echo PATH
/Users/zero/.virtualenvs/prueba/bin:/Users/zero/bin:/Users/zero/.toolbox/bin:/Users/zero/Library/Python/3.8/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/Applications/Visual Studio Code.app/Contents/Resources/app/bin

In both, zsh and bash.

export DOCKER_HOST=ssh://zero@localhost

error during connect: Get http://docker/v1.24/containers/json: command [ssh -l zero -- localhost docker system dial-stdio] has exited with exit status 127, please make sure the URL is valid, and Docker 18.09 or later is installed on the remote host: stderr=zsh:1: command not found: docker

which docker
/usr/local/bin/docker

uname -a
Darwin 147dda48aad1.ant.amazon.com 19.6.0 Darwin Kernel Version 19.6.0: Tue Jan 12 22:13:05 PST 2021; root:xnu-6153.141.16~1/RELEASE_X86_64 x86_64

docker --version
Docker version 20.10.0, build 7287ab3

In case of remote docker machines I have no problem, but trying to ssh against my self to make some tests/poc don't.

[Tylerc230]

I believe this is because PATH is not set when using ssh (not a login shell). This fails ssh <username>@<ip> 'docker info' but this works ssh <username>@<ip> '/usr/local/bin/docker info'

[zylyye]

I have encountered the same problem, that is because when we execute ssh command directly (ssh user@host command), the shell is started non-interactively and uses it's default PATH(you could see it by using ssh user@host env | grep PATH), so the fundamental question is how to set PATH of non-interactively shell:

1. edit /etc/ssh/sshd_config and set PermitUserEnvironment yes
2. edit ~/.ssh/environment and add PATH=/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin
3. restart your sshd server (on MacOS using sudo launchctl stop com.openssh.sshd; sudo launchctl start com.openssh.sshd)