docker-sshd && kube-sshd

docker-sshd

with docker-sshd, you can ssh into docker containers from anywhere, just like docker exec -ti CONTAINER_ID /bin/bash on the docker host machine.

+-------------+                                                                 
|             |    ssh CONTAINER1@docker-sshd      +--------------------+       
|     ops     +------------------------------------>                    |       
|             |                                    |    docker-sshd     |       
+-------------+                                    |                    |       
                                                   +----------------+---+       
                                                                    |           
                                                                    |           
                              docker exec -ti CONTAINER1 /bin/bash  |           
                                                                    |           
                +--------------------------------------------------------------+
                |                                                   |          |
                | Docker   +------------+  +------------+    +------v-----+    |
                |          |            |  |            |    |            |    |
                |          | CONTAINER3 |  | CONTAINER2 |    | CONTAINER1 |    |
                |          |            |  |            |    |            |    |
                |          +------------+  +------------+    +------------+    |
                |                                                              |
                +--------------------------------------------------------------+

kube-sshd

with kube-sshd, you can ssh into kubenetes pod from anywhere, just like kubectl exec -ti POD /bin/bash.

+-------------+                                                                 
|             |    ssh POD1@kube-sshd              +--------------------+       
|     ops     +------------------------------------>                    |       
|             |                                    |    kube-sshd       |       
+-------------+                                    |                    |       
                                                   +----------------+---+       
                                                                    |           
                                                                    |           
                             kubectl exec -ti POD1 /bin/bash        |           
                                                                    |           
                +--------------------------------------------------------------+
                |                                                   |          |
                | k8s      +------------+  +------------+    +------v-----+    |
                |          |            |  |            |    |            |    |
                |          |    POD1    |  |    POD2    |    |    POD3    |    |
                |          |            |  |            |    |            |    |
                |          +------------+  +------------+    +------------+    |
                |                                                              |
                +--------------------------------------------------------------+

Install

go get github.com/tg123/docker-sshd/cmd/docker-sshd

Quick start

1. start a container named CONTAINER1

```
docker run -d -t --name CONTAINER1 ubuntu top
bd78d93154cff5e8b40d19b1676670a49f582d2522384ecfe0d9e7d60846891e
```

1. start docker-sshd

```
docker-sshd
```

1. connect to container with ssh

```
ssh CONTAINER1@127.0.0.1 -p 2232
root@bd78d93154cf:/#
```

Options

--address value, -l value     listening address (default: "0.0.0.0")
--port value, -p value        listening port (default: 2232)
--server-key value, -i value  server key files, support wildcard (default: "/etc/ssh/ssh_host_ed25519_key")
--command value, -c value     default exec command (default: "/bin/sh")

Docker related Environment

• DOCKER_HOST to set the URL to the docker server, default unix:///var/run/docker.sock.
• DOCKER_API_VERSION to set the version of the API to use, leave empty for latest.
• DOCKER_CERT_PATH to specify the directory from which to load the TLS certificates (ca.pem, cert.pem, key.pem).
• DOCKER_TLS_VERIFY to enable or disable TLS verification (off by default).

see https://pkg.go.dev/github.com/docker/docker/client#FromEnv for more detail

Connecting from vscode

Make sure your container meet the prerequisites. Additionally, install nc to your container to have tcp redirect working