Error connecting to docker daemon (does docker ps work?)

Question

I wanted to create a docker bench with basic setup and I use the basic code given at the Github link for Docker Benche Security. The code is as follows :

docker run --rm --net host --pid host --userns host --cap-add audit_control \
    -e DOCKER_CONTENT_TRUST=$DOCKER_CONTENT_TRUST \
    -v /etc:/etc:ro \
    -v /usr/bin/containerd:/usr/bin/containerd:ro \
    -v /usr/bin/runc:/usr/bin/runc:ro \
    -v /usr/lib/systemd:/usr/lib/systemd:ro \
    -v /var/lib:/var/lib:ro \
    -v /var/run/docker.sock:/var/run/docker.sock:ro \
    --label docker_bench_security \
    docker/docker-bench-security

But I am getting an error saying

Error connecting to docker daemon (does docker ps work?)

Anybody has through solution for this with steps ?

Thank you very much in advance

Docker Version :

Client: Docker Engine - Community

Cloud integration: 1.0.7
Version: 20.10.2
API version: 1.41
Go version: go1.13.15
Git commit: 2291f61
Built: Mon Dec 28 16:14:16 2020
OS/Arch: windows/amd64
Context: default
Experimental: true

Server: Docker Engine - Community

Engine:
Version: 20.10.2
API version: 1.41 (minimum version 1.12)
Go version: go1.13.15
Git commit: 8891c58
Built: Mon Dec 28 16:15:28 2020
OS/Arch: linux/amd64
Experimental: false
containerd:
Version: 1.4.3
GitCommit: 269548fa27e0089a8b8278fc4fc781d7f65a939b
runc:
Version: 1.0.0-rc92
GitCommit: ff819c7e9184c13b7c2607fe6c30ae19403a7aff
docker-init:
Version: 0.19.0
GitCommit: de40ad0

Linux Kernel Version : 3.1.6-340.x86_64

Error connecting to Docker Daemon

So did you try what was suggested? What does `docker ps` give you? If it doesn't work, then you've got something wrong with your Docker setup. Maybe you just don't have your environment set to use a healthy Docker environment. You might try `docker context show`, especially if you have multiple Docker environments, and might have one of them powered down. That's often what leads to this problem. When faced with a problem in connection with a complex command like yours, it's best to fall back to simpler operations to figure out what's going on. — CryptoFool, Mar 07 '21 at 07:04
Docker ps works for me. Because I use "docker run -itd to start a container first. Then I try to implement the code. So "docker ps" gives me the list of the running containers. — Tahmid Hossain, Mar 07 '21 at 08:26
Glancing at the repository, it's just a couple of shell scripts; I'm not sure why it's packaged in Docker, given how much host access it requires. Can you run it with `sudo` directly on the host? (Are you trying to develop this, or just run a prepackaged application?) — David Maze, Mar 07 '21 at 11:00
Yup. I tried working with `sudo`. It still did not work. I am just trying to run a prepackaged application. If I wanted to develop, I might not have faced this issue. — Tahmid Hossain, Mar 08 '21 at 02:18

score -1 · Answer 1 · answered Mar 07 '21 at 09:32

The problem occurs in the shell script docker-bench-security.sh that runs inside the container when you start it. Here's the block of code in question, which appears to be an early sanity check:

# Ensure we can connect to docker daemon
if ! docker ps -q >/dev/null 2>&1; then
  printf "Error connecting to docker daemon (does docker ps work?)\n"
  exit 1
fi

I'm on a Mac, and I get the same error doing simply:

docker run docker/docker-bench-security

so it has nothing to do with any of your parameters. I'm fairly new to Docker, and have never tried utilizing the docker command from inside a container, so I'm of no help here. I googled a bit, looking for an answer. I didn't find one. I found a few GitHub posts asking about the same problem, but no answers ever arrived on those threads:

https://github.com/docker/docker-bench-security/issues/197

https://github.com/docker/docker-bench-security/issues/123

Maybe someone will come along here and give you a better answer. I hope so. If not, there are some clues in these threads as to where you might want to look next for an answer.

Error connecting to docker daemon (does docker ps work?)

1 Answers1