Docker image stopped working after upgrading docker - docker

I've been using for years a containerized version of a web-application on my development laptop. Usually I do something like
docker run -it -d --rm -h app.localhost my-app
and, having added app.localhost to my hosts file, going to http://app.localhost everything works. Yesterday an update came for docker and I'm no longer able to do that. Running the image with the same command line options and trying to connect to the application I get a browser error page and checking the logs in the container shows no request at all got to the web server. Running curl http://app.localhost in a terminal works fine, and I've been able to fix the problem changing the my command line options to
docker run -it -d --rm -p 80:80 -h app.localhost my-app
i.e. explicitly exposing port 80.
Can anyone explain what went wrong? And why would curl and my web browser behave differently?
Edit: to clarify: I'm referring to an update of the docker packages for my OS (Ubuntu 18 if that matters).

Related

How to connect to docker via VNC when the docker image is not made by you?

I'm trying to get started with PANDA RE, a framework developed by MIT Lincoln Lab for Reverse Engineering. Their website says that beginners should try the tool through docker first. Therefore, I pulled their image and got it to run with the command docker run -p 5900:5900 --rm pandare/panda panda-system-i386. The log says VNC server running on 127.0.0.1:5900.
However, if I use Remmina to connect via VNC, it says "VNC server closed connection."
Any tips on fixing this?
If it helps, docker container ls prints 0.0.0.0:5900->5900/tcp for this container
If you run the --help you will get
The default display is equivalent to
"-vnc localhost:0,to=99,id=default"
So, in order to get the panda to listen to 0.0.0.0 you will need to run it with
docker run -p 5900:5900 -ti --rm pandare/panda panda-system-i386 -vnc 0.0.0.0:0,to=99,id=default

How to run sitespeed.io in apache/ngnix server?

I have recently heard about sitespeed.io and started using it to measure performance of my site.
I am running it in a docker container on my gcp cloud instance.
The problem is everytime i run the command it stores the result in a particular directory sitespeed-result and then I need to copy the whole thing on my local windows machine to view index.html file.
Is it possible to run this on a server like apache? I mean for example I can run an apache container on my docker host but how do i map this sitespeed io result so that it can be available using http://my-gcp-instance:80 where my apache container is running on port 80.
sudo docker run -v "$(pwd)":/sitespeed.io sitespeedio/sitespeed.io:13.3.0 https://mywebsite.com
Sorry for posting thr question this but I got it working.
sudo docker run -dit --name my-apache -p 8080:80 -v "$(pwd)":/usr/local/apache2/htdocs/ httpd:2.4
(pwd) is where i am storing the sitespeed results.

How to set up xdebug / docker / drupal stack?

My objective is to be able to debug a tricky piece of Drupal 8 code. My experience with docker is very limited (beginner level). I have a database docker container running which I spinned like this:
docker run --name drupalMulti-database -p 3306:3306 -v `pwd`:/var/lib/mysql -d percona:latest
Then, my drupal 8 docker container is connected to the container above like this:
docker run -e XDEBUG_CONFIG="remote_host=10.1.2.74" --name drupalMulti -p 8484:80 -p 8453:443 --link drupalMulti-database:mysql -v `pwd`:/var/www/html/ -d gitlab.OUR-COMPANY-NAME.com:4999/dev/PATH-TO-OUR-DRUPAL-CONTAINER
I am wondering how can I configure either PhpStorm or VsCode to work properly with xdebug, so I could debug my drupal code: set breakpoints, step into the code etc? Assume that I have no access to modify the existing docker images, but my Drupal image already has xdebug pre-installed.
(Running Drupal 8 / php 7.2 / mysql 5.7)
Try setting xdebug.remote_host to host.docker.internal if the docker is running locally. You also would need to have a copy of the project stored locally to be able to debug it via PhpStorm. See https://www.jetbrains.com/help/phpstorm/configuring-xdebug.html#configuring-xdebug-docker and https://www.jetbrains.com/phpstorm/documentation/debugging/

Docker connection refused when started with -ti bash

I am new to docker and I tried to run the linuxconfig/lemp-php7 image. Everything worked fine and I could access the nginx web server installed on the container. To run this image I used this command:
sudo docker run linuxconfig/lemp-php7
When I tried to run the image with the following command to gain access over the container through bash I couldn't connect to nginx and I got the connection refused error message. Command: sudo docker run -ti linuxconfig/lemp-php7 bash
I tried this several times so I'm pretty sure it's not any kind of coincidence.
Why does this happen? Is this a problem specific to this particular image or is this a general problem. And how can I gain access to the shell of the container and access the web server at the same time?
I'd really like to understand this behavior to improve my general understanding of docker.
docker run runs the specified command instead of what that container would normally run. In your case, it appears to be supervisord, which presumably in turn runs the web server. So you're preventing any of that from happening.
My preferred method (except in cases where I'm trying to debug cases where the container won't even start properly) is to do the following after running the container normally:
docker exec -i -t $CONTAINER_ID /bin/bash

Get TeamCity running on Docker

I'm brand new to both TeamCity and Docker. I'm struggling to get a Docker container with TeamCity running and usable on my local machine. I've tried several things, to no avail:
I installed Docker for Mac per instructions here. I then tried to run the following command, documented here, for setting up teamcity in docker:
docker run -it --name teamcity-server-instance \
-v c:\docker\data:/data/teamcity_server/datadir \
-v c:\docker\logs:/opt/teamcity/logs \
-p 8111:8111 \
jetbrains/teamcity-server
That returned the following error: docker: Error response from daemon: Invalid bind mount spec "c:dockerdata:/data/teamcity_server/datadir": invalid mode: /data/teamcity_server/datadir.
Taking a different tack, I tried to follow the instructions here - I tried running the following command:
docker run -it --name teamcity -p 8111:8111 sjoerdmulder/teamcity
The terminal indicated that it was starting up a web server, but I can't browse to it at localhost, nor at localhost:8111 (error ERR_SOCKET_NOT_CONNECTED without the port, and ERR_CONNECTION_REFUSED with the port).
Since the website with the docker run command says to install Docker via Docker Toolbox, I then installed that at the location they pointed to (here). I then tried the
docker-machine ip default
command they suggested, but it didn't work, error "Host does not exist: "default"". That makes sense, since the website said the "default" vm would be created by running Docker Quickstart and I didn't do that, but they don't provide any link to Docker Quickstart, so I don't know what they are talking about.
To try to get the IP address the container was running on, I tried this command
docker inspect --format='{{.Name}} - {{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' $(docker ps -aq)
That listed the names of the running containers, each followed by a hyphen, then nothing. I also tried
docker ps -a
That listed running contaners also, but didn't give the IP. Also, the port is blank, and the status says "exited (130) 4 minutes ago", so it doesn't seem like the container stayed alive after starting.
I also tried again with port 80, hoping that would make the site show at localhost:
docker run -it --name teamcity2 -p 80:80 sjoerdmulder/teamcity
So at this point, I'm completely puzzled and blocked - I can't start the server at all following the instructions on hub.docker.com, and I can't figure out how to browse to the site that does start up with the other instructions.
I'll be very grateful for any assistance!
JetBrains now provides official docker images for TeamCity. I would recommend starting with those.
The example command in their TeamCity server image looks like this
docker run -it --name teamcity-server-instance \
-v <path to data directory>:/data/teamcity_server/datadir \
-v <path to logs directory>:/opt/teamcity/logs \
-p <port on host>:8111 \
jetbrains/teamcity-server
That looks a lot like your first attempt. However, c:\docker\data is a Windows file path. You said you're running this on a mac, so that's definitely not going to work.
Once TeamCity starts, it should be available on port 8111. That's what -p 8111:8111 part of the command does. It maps port 8111 on your machine to port 8111 in the VM Docker for Mac creates to run your containers. ERR_CONNECTION_REFUSED could be caused by several things. Two most likely possibilities are
TeamCity could take a little while to start up and maybe you didn't give it enough time. Solution is to wait.
-it would start the TeamCity container in interactive mode. If you exit out of the terminal window where you ran the command, the container will also probably terminate and will be inaccessible. Solution is to not close the window or run the container in detached mode.
There is a good overview of the differences between Docker for Mac and Docker Toolbox here: Docker for Mac vs. Docker Toolbox. You don't need both, and for most cases you'll want to use Docker for Mac for testing stuff out locally.

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