Secrets example doesnt work on server "Error: open /.s0: file does not exist"

[Joly0]

Hey, i am trying to run the example compose from here https://github.com/docker/mcp-gateway/tree/main/examples/secrets on my server running unraid (slackware linux) and have only changed the the env variable in the .env file.
When the cotnainer starts it throws this error:

- Reading configuration...
  - Reading catalog from [https://desktop.docker.com/mcp/catalog/v2/catalog.yaml]
  - Reading secrets [github.personal_access_token]
couldn't read secret github.personal_access_token: reading secrets exit status 1: Error: open /.s0: file does not exist
- Configuration read in 705.006955ms
- Using images:
  - ghcr.io/github/github-mcp-server@sha256:3efa93289a7c6e513145535df8776dd4c8ccf5f2ceafcde76d4571d2533b6a3c
> Images pulled in 3.612372ms
- Verifying images []
> Images verified in 688.210274ms
- Those servers are enabled: github-official
- Listing MCP tools...
  - Running ghcr.io/github/github-mcp-server with [run --rm -i --init --security-opt no-new-privileges --cpus 1 --memory 2Gb --pull never -l docker-mcp=true -l docker-mcp-tool-type=mcp -l docker-mcp-name=github-official -l docker-mcp-transport=stdio --network mcp_gateway_default -e GITHUB_PERSONAL_ACCESS_TOKEN]
- github-official: WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
- github-official: GitHub MCP Server running on stdio
  > github-official: (73 tools) (1 prompts) (5 resourceTemplates)
> 73 tools listed in 430.4887ms
> Initialized in 1.828266768s
> Start stdio server

I also tried running this in a test container that had docker installed (apt install --no-install-recommends docker.io) and there i get a clearer error when trying to acess the ´docker mcp secrets set/ls´ command:

root@a1081a6a2d61:/app# docker mcp secret ls
Get "http://localhost/secrets": dial unix /root/.docker/desktop/jfs.sock: connect: no such file or directory

this is even the case when i make sure that the variable "DOCKER_MCP_IN_CONTAINER" is set to 1

So seems like there is still some kind of dependency to docker desktop for the secrets as far as i understand (i am not certain about this).

[slimslenderslacks]

Thanks for reporting! On line 6 of the example, we are configuring the gateway to first check docker desktop secrets, if they are available, and then fallback to to the compose secret mount if this fails.

The docker-desktop: check could be removed but even if we leave it in this example, we should now be falling back to just using the secret mount here.

The current compose.yaml example is not configured to automatically pull new tags but docker pull docker/mcp-gateway:latest should fix this. I think we should probably update the pull_policy on this particular example (to always).

[Joly0]

Hey, i tried to pull the latest image and i also tried to remove that line 6 from the compose, but it didnt change much. I am still hitting the same issue. Is this to be expected?

[slimslenderslacks]

Thanks for checking. This is not expected. I'll need to see if I can reproduce this. If you don't mind, I'll rename this to indicate that it's problem with the Community Edition of Docker because I think this is something specific to running without Docker Desktop (which should work!)