I have set up docker on my Mac using Kinematic. I have a mysql container running.
So, the 'schematic', I believe, looks like this: (Mac1 (VirtualBox Docker Host (MySQL Container))).
Mac1 IP: 10.10.10.100
MySQL Container: 192.168.99.100 running on port 32500 (mapped to 3306)
I can access the MySQL server via 192.168.99.100:32500 from Mac1 without any issues.
Now, when I go to Mac2 on my network, I cannot access the MySQL container.
So, Mac2 IP: 10.10.10.200 cannot see 192.168.99.100:32500. Mac2 gets a ping response, but not sure if it is getting all the way to the MySQL Container.
I'm thinking of installing a proxy on Mac1, but wanted to check first.
None of the questions posed here seemed to account for a Kinematic install on a Mac, and the ones referring to boot2docker didn't address the question either.
Any insights would be most welcome! Thanks in advance.
If you are looking for the simplest way to expose a container port to your network, you could map a virtual box port onto the mac1 and access it from outside.
Related
I know there are similar questions on the SO but many of the suggestions have not worked for me. I'm running Docker Desktop for Mac and I startup a docker container I've built that has ssh configured and running (I use these to connect to AWS, Azure etc). I startup the container with something like (the ubc/jlbase/jlbase image has ssh configure... and the following all works on a linux machine with docker0 network in place)
docker run -P --name test -d ubc/jlbase/jlbase
docker inspect test |grep IP
ping -c *the_ip_from_above*
does not connect. From what I can find, this is a known issue with Docker on Mac... but the help and links I've found don't seem to solve the problem. Can someone tell me what I've missed?
You can say that this is a know feature of Docker on Mac, not an issue. Docker on Mac is running on a virtual machine inside macOS, so the IP address you receive is the IP of the container inside the VM, not on macOS.
To address the two issues from the question:
How to enable ssh
To be able to ssh on your container, you will need to have the sshd running in the container and to publish the port 22. Check here to see how you can try this with a container that is already prepared
How to ping
Since the docker is running inside a VM, to be able to route traffic to the containers, you will need to setup the network layer to route the traffic. One approach is to create a tunnel between the VM and the machine.
This is much more complex setup and will require a help of a CNF (Conteinerized Network Function). One of the simplest CNF that was created just for this problem is soctun which creates a tunnel between the host and the docker network layer.
Hi what I am actually trying is to connect remotly from a MySQL Client in Windows Subsystem for Linux mysql -h 172.18.0.2 -P 3306 -u root -p and before that I started the Docker Container as follows: docker container run --name testdb --network testnetwork -p 3306:3306 -e MYSQL_ROOT_PASSWORD=mysqlRootPassword -e MYSQL_DATABASE=localtestdb -d mariadb/server.
The purpose why I put the container in a own network, is because I also have a dockerized Spring Boot Application (GraphQL-Server) which shall communicated with this db. But always when I try to connect from my built-in mysql client, in my Windows Subsystem for Linux, with the above shown command. I got the error message: ERROR 2002 (HY000): Can't connect to MySQL server on '172.18.0.2' (115).
What I already tried, to solve the problem on my own is, look up whether the configuration file line (bind-address) is commented out. But it wont work. Interestingly it already worked to set up a docker container with MariaDB and connect from the outside, but now when I try exactly the same, only with the difference that I now put the container in a own existing network, it wont work.
Hopefully there some one out there which is able to help me with this annonying problem.
Thanks!
So far,
Daniel
//edit:
Now I tried the solution advice from a guy from this topic: How to configure containers in one network to connect to each other (server -> mysql)?. Futhermore I linked my Spring Boot (server) application with the "--link databaseContainerName" parameter to the MariaDB container.
Now I am able to start both containers without any error, but I am still not able to connect remotly to the MariaDB container. Which is now running in a virtual docker network with his own subnet.
I explored this recently - this is by design - container isolation. Usually only main (service httpd) host is accessible externally, hiding internal connections (hosts it communicates to deliver response).
Container created in own network is not accessible from external adresses, even from containers in the same bridge but other network (172.19.0.0/16).
Your container should be accessible on docker host address (127.0.0.1 if run locally) and mapped ("-p 3306:3306") port - 3306. But of course it won't work if many running db containers have the same mapping to the same host port.
Isolation is done using firewall - iptables. You can list rules (iptables -L) to see that - from docker host level.
You can modify firewall to allow external access to internal networks. I used this rule:
iptables -A DOCKER -d 172.16.0.0/12 -j ACCEPT
After that your MySQL containerized engine should be accessible using internal address 172.18.0.2 and source (not mapped) port 3306.
Warnings
it disables all isolation, dont't use it on production;
you have to run this after every docker start - rules created/modified by docker on the fly
not every docker container will respond on ping, check it from docker host (linux subsystem in this case) first, from windows cmd later
I used this option (in docker.service) to make rule permanent:
ExecStartPost=/bin/sh -c '/etc/iptables/accept172_16.sh'
For docker on external(shared in lan) host you should use route add (or hosts file on your machine or router) to forward 172.x.x.x addresses into lan docker host.
Hint: use portainer project (with restart policy - always) to manage docker containers. It's easier to see config errors, too.
I have set up a couple of containers that interact with each other. The main application container runs on --network = host because it queries several mySQL containers running on different ports exposed on the host network.
I am trying to hit the application on the host but get an error:
curl: (7) Failed to connect to 0.0.0.0 port 36081: Connection refused
I am working on Docker installed on MacOS.
I have read several questions that indicate that docker on MacOS runs on a VM. But what is the workaround to access the application from the host? Any way to get the IP of the said VM?
You cannot use --network=host on Mac to connect via host ports but binding to host port using -p options works.
https://docs.docker.com/docker-for-mac/networking/#/there-is-no-docker0-bridge-on-osx
I WANT TO CONNECT TO A CONTAINER FROM THE MAC
Port forwarding works
for localhost; --publish, -p, or -P all work. Ports exposed from Linux
are forwarded to the host.
Our current recommendation is to publish a port, or to connect from
another container. This is what you need to do even on Linux if the
container is on an overlay network, not a bridge network, as these are
not routed.
For your use case,
You need to create a docker network and attach both the DB and application containers to this network. Then the containers will be able to talk to each other by their name. You can also publish the application container port so that you can access it from your host.
https://docs.docker.com/network/bridge/
Instead of creating the network, attaching the containers to the network etc manually, you can use docker-compose.
https://docs.docker.com/compose/
I'm running a CentOS-based container on Docker for Windows and trying to connect to an http service running on port 8545 of my host environment.
I've tried this, attempting a variety of suspected host names and IP addresses:
curl http://localhost:8545
But the error message I get is "curl: (7) Failed connect to localhost:8545; Connection refused"
How should I figure out what IP Address to use? Is there anything I need to configure as far as allowing the port number to be accessed from inside the container?
Localhost is not working yet I think with Docker for Windows.
There is few things you can try. First you can add EXPOSE 'portnumber' in the dockerfile so the container will listen on this port. You can also use docker run with -p 8545:8545, it will map the port of the container and the host.
To get the Ip address of the container you can use:
docker inspect -f "{{ .NetworkSettings.Networks.nat.IPAddress }}" containername
You can access the host using its ip but localhost/127.0.0.1 won't work (they will resolve to the Linux VM that is part of docker for windows). If you use the default network settings, your host should be reachable on 10.0.75.1 from your container
In my job I working with docker and the option --net=host working like a charm forwarding the docker container ports to the machine. This allows me to adding grunt tasks that use certain ports by example:
A taks for serving my coverage report in a port 9001
A local deployed version of my app served in the port 9000
A watch live reload the port 35729
For Unit testing runner use the 9876 port
When I begin to use Docker in Mac, the first problem that i had was: The option --net=host don't work anymore.
I researched and I understand why this is not possible (Docker in Mac runs in a own virtual machine) and my momentary solution it's use the -p option for expose the ports, but this limit to me to add more and more task that use ports because i need run the explicit -p command for each port that i need expose.
Anyone with this same problem? How to dealing with this ?
Your issue is most probably that you are using dockertoolbox or dhingy/dlite or anything else providing a full-fledged linux VM, which then hosts docker to run your container inside this VM. This VM has, of course, its own network stack and own IP on the host, and thats were your tools will have issues with. The exposed ports of the container are not exposed to OSX host localhost, but rather OSX Docker-VM-ip.
To solve those issues elegantly
Expose ports to OSX localhost from the container
First, use/install docker-for-mac https://docs.docker.com/engine/installation/mac/ instead of dockertoolbox or others. Its based on a special xhyve stack which reuses your hosts network stack
when you now do docker run -p 3306:3306 percona it will bind 3306 on the osx-host-localhost, thus every other osx-tool trying to attach to localhost:3306 will work ( very useful ) just as you have been used to it when you installed mysql using brew install mysql or likewise
If you experience performance issues with code shares on OSX with docker containers, check http://docker-sync.io - it is compatible with docker-for-mac ( hint: i am biased on this one )
Export ports from the OSX-host to a containter
You do not really export anything in particular, you rather make them accessable as a whole from all containers ( all ports of the OSX-host-localhost)
If you want to attach to a port you offered on the OSX host, from within a container, e.g. during a xdebug session were your IDE listens on port 9000 on the OSX-host-localhost and the container running FPM/PHP should attach to this osx-localhost:9000 on the mac, you need to do this: https://gist.github.com/EugenMayer/3019516e5a3b3a01b6eac88190327e7c
So you create a dummy loopback ip, so you can access your OSX-host ports from without containers using 10.254.254.254:9000 - this is portable and basically gives you all you need to develop like you have used to
So one gives you the connectivity to container-exposed ports to apps running on the mac and trying to connect to localhost:port
And the second the inverse, if something in the container wants to attach to a port on the host.
One workaround, mentioned in "Bind container ports to the host" would be to use -P:
(or --publish-all=true|false) to docker run which is a blanket operation that identifies every port with an EXPOSE line in the image’s Dockerfile or --expose <port> commandline flag and maps it to a host port somewhere within an ephemeral port range.
The docker port command then needs to be used to inspect created mapping.
So if your app can use docker port <CONTAINER> to retrieve the mapped port, you can add as many containers as you want and get the mapped ports that way (without needed an "explicit -p command for each port").
Not sure if docker for mac can support bi-directional connection later https://forums.docker.com/t/will-docker-for-mac-support-bi-directional-connection-between-host-and-container-in-the-future/19871
I have two solution:
you can write a simple wrapper script and pass the port you want to expose to the script
use vagrant to start a virtual machine with network under control.