I'm running Ubuntu 20.4. and installed Docker by following the steps from the docs https://docs.docker.com/engine/install/ubuntu/#install-using-the-repository .
I installed Rider from Jetbrains Toolbox and want to setup Docker for my project. The Docker plugin is installed by default. I made sure that Docker is running via systemctl status docker.
I followed this guide on how to setup Docker for Rider https://blog.jetbrains.com/dotnet/2018/07/18/debugging-asp-net-core-apps-local-docker-container/ but unfortunately I get this error
Cannot connect:
io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection
refused: localhost/127.0.0.1:2375 caused by:
java.net.ConnectException: Connection refused
What is missing or wrong?
In that dialog, check "Unix socket".
This will contact the Docker daemon via the special file /var/run/docker.sock. You may need to adjust your user's permissions (typically by making yourself a member of the docker group) to get access to that file.
The "TCP socket" option is for an unusual and hard-to-securely-configure mode of connecting to Docker. (Anyone who can run any docker command can run a container as root, and bind-mount any file from the host; you really don't want to make this level of access network-accessible.) You shouldn't ever need the TCP socket mode..
Related
I'm using Jenkins on Docker on my local Mac Machine.
And I'm running another Docker on ubuntu VirtualBox. So now, there are 2 docker machines. one is on my mac machine and one is on my Ubuntu VirtualBox machine. I'm running Jenkins on Mac Docker. Now in the Jenkins pipeline, I want to build an image on my ubuntu machine.
I've configured Jenkins docker cloud and in the docker host URL, it is connected to the ubuntu docker-machine.
But while building a new image, I'm getting the error. Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?
I've tried even adding ExecStart=/usr/bin/dockerd -H tcp://0.0.0.0:4243 -H unix:///var/run/docker.sock
at /lib/systemd/system/docker.service
WHen i check ps -aux,
Can someone please help me out?
help is appreciated.
First personally if I had a setup like that I would not bother connecting to the remote docker and would just install a Jenkins agent on the ubuntu machine and make it talk to the Jenkins master.
But if you want to do it they way you have it set up right now we a Jenkins talking from inside out one docker host into another docker host I suggest looking into the following:
Your Jenkins master and the ubuntu machine a very isolated they might as well just be on different machines not even in the same room. Unix domain sockets, the ones that are identified by unix://* are made for communicating within a single local OS kernel, trying to bridge them into remote machine will lead to disaster.
So the only way Jenkins could communicate to the remote host is via a remote protocol like TCP. Most of the time when you install docker with the default settings it doesn't even listen to TCP at all, mostly for security reasons.
First thing you should do is to configure a docker inside of the ubuntu machine to listen on TCP port and accept connections from remote hosts. You can use netstat -nat to see if anything is listening on TCP 4243. When things are configured correctly you see the line that stats with 0.0.0.0:4243 or something like that in the output of the nestat
Second you need to make sure your the firewalls/iptables/netfilter configuration on the Ubuntu host lets in connections from outside. A good test to try is to telnet <ubuntu-ip> 4243 from a terminal session on your Mac.
Then you need to make sure you that docker networking is configured correctly so that connections from the inside of the container that is running Jenkins end up on your ubuntu box. To test you need to exec -it into your jenkins container and repeat the telnet test. On modern linuxes telnet is usually not installed, so you can use curl -vvv which will always end up with an error, so just look at the verbose output to see if the error because things cannot communicate (timeout, connection reset etc) or the error occurs because your curl tried to talk HTTP to docker and got gibberish response. In the later case you can consider things to be set up correctly.
Finally you need to tell Jenkins Docker to communicate to the remote docker via TCP. Usually that is given on the command line to your docker run, docker ps, docker exec
I've configured it by defining the slave label in my Jenkins Pipeline.
Jenkins agents run on a variety of different environments such as physical machines, virtual machines, Kubernetes clusters, and Docker images.
In your Jenkins Pipeline or In your JenkinsFile, you've to set the agent accordingly to what you're using either using Docker image or any virtual machine.
Also Thank you so much #Vlad, all the things you told me, were really helpful.
On running docker images, I am getting error
error during connect: Get http://%2F%2F.%2Fpipe%2Fdocker_engine/v1.40/images/json:
open //./pipe/docker_engine: The system cannot find the file specified.
In the default daemon configuration on Windows, the docker client must be
run elevated to connect. This error may also indicate that the docker
daemon is not running.
I am on Windows 10 Home and have tried to install/reinstall Docker but I keep getting the error. Things were working fine an hour back!
Can you check if you have a VM running under docker-machine? You can run the below command:
docker-machine ls
And if you haven't installed docker-machine, please install it.
Ref:- https://docs.docker.com/toolbox/toolbox_install_windows/
Note:- Make sure enabled the BIOS virtualization.
I want to work in a container in a remote server.
But it doesn't work.
Environment:
Local: Windows 10
Local Terminal for ssh: WSL in Windows 10
Server: Ubuntu 18.04
I checked these two articles.
https://code.visualstudio.com/docs/remote/containers-advanced
https://code.visualstudio.com/docs/containers/ssh
I followed these steps.
I installed [Remote Development] extension in VS Code.
Remote-SSH: Connect to host. It works fine.
I Installed [Docker] extension on the remoter server.
Now I can see my containers and images in a docker tab.
I clicked one container and clicked [Attach Visual Studio Code] and it says There are no running containers to attach to.
I resolved this problem by switching to the remote server's Docker context on my local machine:
docker context create some-context-label --docker "host=ssh://user#remote_server_ip"
docker context use some-context-label
docker ps
# A list of remote containers on my local machine! It works!
After that:
Connect via Remote-SSH to the container server
Right click relevant container -> the "Attach Visual Studio Code"
That works for me.
(Note: One would think that I should be able to just use my local VSCode (skip step 1) to connect to said remote container after switching my local context, but VSCode complains Failed to connect. Is docker running? in the Docker control pane.)
I solve this issue using SSH tunneling following the steps found in https://florian-kriegel.de/blog/?p=234
Summarizing:
Set (or add) "docker.host": "tcp://localhost:23750" in settings.json
in VSCode.
Open a SSH tunnel like this in your local machine
changing the user and hostname by the remote machine (where the docker daemon is running) credentials:
ssh -NL localhost:23750:/var/run/docker.sock user#hostname.
Now, in the docker tab, you will be able to see and attach to containers in the remote machine.
Note that the Remote SSH Extension is not used in this case.
This might sound very strange, but for me, I had to open a folder on the remote SSH server prior to using the Remote Containers extension in VS Code. If I didn't do that, then it would constantly try to find the docker service running locally, even though the terminal tab was connected to the remote SSH server.
This seems very weird, because if you're conncted via SSH in VS Code, then the extension should assume you're trying to attach to the container on the remote server. Shouldn't have to open a remote folder first.
By "opening a folder" on the remote server, the Remote Containers extension was then able to attach VS code to the container running on the remote SSH server. I didn't have to do any of the steps in any of those articles. Just simply use Remote SSH to connect VS Code remotely via SSH, open a folder, and then use Remote Containers.
Solution using the "Remote SSH" and the "Remote Explorer" extension in Visual Studio Code.
Following the steps above (https://stackoverflow.com/a/61728799/11687201) I figured out how to make use of the SSH Remote and Remote Explorer Extension. The first step is the same as above:
Open the settings.json file in VSCode, press F1 and select ">Preferences: Open Settings (JSON)" and add/edit the following line:"docker.host": "tcp://localhost:23750"
Open the ssh config file, click on the "Remote Explorer" Extension, then click on the "SSH Targets" "Configure" button and open the ssh config file.
Add the following line to your ssh connection:
LocalForward localhost:23750 /var/run/docker.sock
Remark: Previously I used the solution described earlier in this thread (https://stackoverflow.com/a/61728799/11687201). I had to reboot both machines the local machine and remote machine before the solution described below worked out.
Afterwards I have to use multiple VSCode Windows:
Local Machine: Start VSCode and use the "Remote Explorer" to connect to the remote machine using a new VSCode window
VSCode window connected to remote (SSH)
→ startup the Docker container of your choice
(I was not able to "Attach Visual Studio Code" from this VSCode window)
VSCode window connected to local machine
→ Click on the "Docker" extension, the docker containers running on the remote get listed. Attach VSCode to a running container using one of the folling options:
Right-click on the desired container and chose "Attach Visual Studio Code"
Press F1 and chose">Remote-Containers: Attach to Running Container..." and select the container of your choice afterwards
A third VSCode window will open being attached to the Docker container.
Pros and cons of this solution
(+) Using the "Remote Explorer" extension I can directly connect and open a previously used project folder on my remote machine with one click
(-) 3 VSCode windows (local machine, remote ssh and remote container) are needed instead of 2 VSCode windows
Do you see the error message as of following?
Failed to connect. Is Docker running?
Error: connect EACCES /var/run/docker.sock
Error Message on VSCode
It's because VSCode uses /var/run/docker.sock of remote host to communicate with the Docker service.
There're two methods.
Method 1. (Secure, Need reboot or logging out) After executing following code of dockerode npm getting error "connect EACCES /var/run/docker.sock" on ubuntu 14.04
Method 2. (Instant effect. Use it if you're not dealing with production server)
Run the following command on SSH console.
sudo chmod o+rw /var/run/docker.sock
For some reason, this problem is fixed for me when I open a folder in the remote window before trying to attach to a container.
I found Daniel's answer really helpful but didn't work for me. I put my two cents.
TL;DR
Create a new docker context for the remote machine where remote container is running.
docker context create some-context-label --docker "host=ssh://user#remote_server_ip"
docker context use some-context-label
Just open VSC, go to Docker (you should have installed the extension) tab and you'll see listed all running containers from the remote context you recently created.
Right click on your desired container and attach visual studio code
You can also use the remote-explorer tab, just select containers from the dropdown at the top left.
Why not to ssh remote host
When attaching visual studio code to a container, you can check logs by clicking the notification Setting up Remote-Containers (show log) at the bottom left. There, you can check that:
...
[26154 ms] Start: Run: ssh some-remote-host /bin/sh
[26160 ms] Start: Run in host: id -un
Here, my guess is that it's trying to ssh to the remote host from itself ,since we already connected via remote-ssh.
If you can reach the remote node running Docker engine via SSH why you need yet another SSH server inside the container? From the host running your container, it is possible and safe to use tty, i.e. attach.
I don't think that this is not a good idea to use SSHD running inside the container although it is possible. To be useful SSHD has to listen to non-conflict port in every container. Otherwise, 2 containers occasionally exposing the same port on the same node will conflict like any other service running on same the node.
Of course, ports can be randomized using -P option but it is not so convenient. It is also less convenient to manage keys and users at the container level than at host level where all machinery is provided by the Host software.
Loading every container with SSHD increases the container size. In Kubernetes, every container is reachable without any SSHD running inside containers via pass Pod->Container because Pod, has IP and containers are attachable by id, i.e. "Docker-host->container"
Step 1 - Docker daemon on the remote machine
make sure your remote Docker daemon can accept connections from your host
for testing purposes, I use the following command on the remote
machine to force Docker daemon to listen on port 4243 on all IPs,
beware this is not secure
There is no support for reading a file from /etc/sysconfig or elsewhere to modify the command line. Fortunately, systemd gives us the tools we need to change this behavior.
The simplest solution is probably to create the file /etc/systemd/system/docker.service.d/docker-external.conf (the exact filename doesn't matter; it just needs to end with .conf) with the following contents:
[Service]
ExecStart=
ExecStart=/usr/bin/dockerd -H tcp://0.0.0.0:4243 -H unix:///var/run/docker.sock
And then:
systemctl daemon-reload
systemctl restart docker
Step 3 - Opening Docker Ports Using FirewallD
firewall-cmd --permanent --zone=public --change-interface=docker0
firewall-cmd --permanent --zone=public --add-port=4243/tcp
firewall-cmd --reload
Step 4 - Set (or add) "docker.host": "tcp://localhost:4243" in settings.json in VSCode.
What are the dependencies and steps to connect to a remote docker container from VSCode? So I can properly compile and run the code with the tools in my container environment?
I have tried to follow the instructions here without much luck:
https://code.visualstudio.com/docs/remote/containers-advanced#_developing-inside-a-container-on-a-remote-docker-host
My setup involves:
Host with VSCode, no docker installed, ssh client installed, ssh keys are in place
Server with VSCode, docker installed, ssh client and server installed
Docker container already running on Server
Host can connect to Server, through VSCode using the Remote Development Version: 0.17.0 extension, through Remote - SSH Version: 0.47.2 extension
Version: 0.47.2
Server can connect to Docker container, through VSCode using the Remote Development Version: 0.17.0 extension, through Remote - Containers Version: 0.83.1 extension.
How do I connect Host to a Running Docker container?
UPDATE 1
Small advance
I have added this line to my ~/.config/Code/User/settings.json file. The option gets highlighed with a message unknown configuration setting
{
...
"docker.host":"tcp://localhost:23750",
...
}
Run this command in another terminal:
ssh -N -L localhost:23750:/var/run/docker.sock <user>#<serveraddr>
And now I can see the running containers in Remote explorer > Containers > Other Containers. However, when trying to connect to it, I get the following error message.
Setting up container with bc1700db049858ba20f1c830bbeff6d6a4e04de58a2b35a61df1016788bc07db
Docker returned an error code 127, signal null, message: Command failed: docker system info
/bin/sh: docker: command not found
So, it appears that docker must be installed on the host machine to prevent the last mentioned error.
Note: docker service does not need to be running in the host (systemctl disable docker)
With this in mind, these are the steps.
Host:
Install docker and ssh client
Add your user to docker group
Install VSCode
Configure Server
(After server config below): edit ~/.config/Code/User/settings.json with
"docker.host":"tcp://localhost:23750",
Configure your ssh keys for the Server
(After every reboot run on terminal: ssh -N -L localhost:23750:/var/run/docker.sock <user>#<serveraddr>)
Run VSCode and install Remote Development extension. Restart VSCode
Now you should see your running containers in VSCode Remote explorer > Containers > Other Containers
Server:
Install docker and ssh server
Install VSCode (this may not be a requirement on the server)
Add your user to docker group and start your container
I realize this was already answered, but I stumbled across this while trying to set this up myself today. I found an additional issue I had appeared to be that my local SSH key had not been added to the agent. I was following the instructions here.
I am running Windows 10 Version 1909 Build 18363.1082.
After doing an ssh-add $Env:USERPROFILE\.ssh\id_rsa and restarting the ssh-agent, I was able to connect to the remote container without having to employ the ssh tunneling method you show above.
I can see my machine … Windows 10 Home
usuario#DESKTOP-GTCQCAR MINGW64 /c/Program Files/Docker Toolbox
$ docker-machine ls
NAME ACTIVE DRIVER STATE URL SWARM DOCKER ERRORS
default - virtualbox Running tcp://192.168.99.101:2376 v18.05.0-ce
But when I try to list the images it tries to connect to a different IP ending in 100, instead of 101 where the docker machine is:
usuario#DESKTOP-GTCQCAR ~
$ docker image ls
error during connect: Get https://192.168.99.100:2376/v1.37/images/json: dial tcp 192.168.99.100:2376: connectex: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.
It can not connect. How can I fix it?
I also faced similar problem after updating from Docker toolbox to Docker for windows.
I solved this problem by deleting all the environment variables starting with Docker.
I am not sure if it will solve your problem as well, but may be it will help someone.
This can also be helpful
Issue can be of having Docker Toolbox installed before changing to Docker for Windows
Uninstalled Docker for windows (make sure Docker Toolbox and VirtualBox are uninstalled as well)
Go to C:\users[USER] directory and remove .docker directory if it is there.
Remove Environmental Variables:
DOCKER_TLS_VERIFY
DOCKER_CERT_PATH
DOCKER_HOST
DOCKER_TOOLBOX_INSTALL_PATH
You might want to restart you computer just to be safe.
Reference: https://forums.docker.com/t/docker-starts-but-trying-to-do-anything-results-in-error-during-connect/49007/5
Check out this great guide: https://docs.docker.com/toolbox/faqs/troubleshoot/
Good luck