I am trying to link my application container to my DB container when sending the JSON task description to the Marathon framework.
I've read up on this question from last year: Linked Docker Containers with Mesos/Marathon
The question is: I know Fig will be able to help me with this but I just wanna know if there is a way to link them on the Marathon framework? HAProxy might work?
If you want to link two containers, they have to run on the same host. Marathon currently does not support that. To me it sounds like you don't really need that. Instead you could just use service discovery mechanisms to make your db accessible to the other service. For this you can use haproxy, or try mesos-dns.
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We have locally set up a docker-container in Docker Engine and I need my coworkers to be able to access it over the network instead of running their own containers and volumes.
Generally this seems possible to do in Docker but I am not sure it actually is.
So if it is possible, how do I let them access it / share it with them?
Please try to answer in simple terms as I'm very new to programming and networking in general.
I have been working on a project where I have had several docker containers:
Three OSRM routing servers
Nominatim server
Container where the webpage code is with all the needed dependencies
So, now I want to prepare a version that a user could download and run. What is the best practice to do such a thing?
Firstly, I thought maybe to join everything into one container, but I have read that it is not recommended to have several processes in one place. Secondly, I thought about wrapping up everything into a VM, but that is not really a "program" that a user can launch. And my third idea was to maybe, write a script, that would download each container from Docker Hub separately and launch the webpage. But, I am not sure if that is best practice, or maybe there are some better ideas.
When you need to deploy a full project composed of several containers.
You may use a specialized tool.
A well known for mono-server usage is docker-compose:
Compose is a tool for defining and running multi-container Docker applications
https://docs.docker.com/compose/
You could provide to your users :
docker-compose file
your application docker images (ex: through docker hub).
Regarding clusters/cloud, we talk more about orchestrator like docker swarm, Kubernetes, nomad
Kubernetes's documentation is the following:
https://kubernetes.io/
I'm currently looking into Mesosphere DCOS to run multiple micro-services using Docker containers. Each micro-services code is already built by my CI into a docker container and uploader to a private container repo.
If I now deploy container A and container B as two different apps using Marathon, how would app A be able to reach app B?
Do I need additional service discovery like Consul?
Would be great if I could have some insights here and maybe even some links / docu to get me started :)
The current solution would be to use some kind service discovery.
DCOS already comes with MesosDNS and it will automatically create an DNS entry for each of your containers started by marathon.
See here for details on using MesosDNS on DCOS.
Hope this helped!
BTW: Feel free to contact the DCOS support directly via the little chat icon in the DCOS UI.
Note: This is a question related to Docker support in Bluemix.
I know how to link a Container with a Container, using --link parameter when starting the second Container with ice run command.
But I haven't found a way to link them, when using a Container Group. I read the docs and check ice command help with no luck.
The scenario I am trying to achieve is to create a front end Container Group linked to a single backend Container. Any idea or suggestion about how to do it?
This is not supported yet in the current ver of IBM Containers.
You can consider, in the mean time, creating yourself the environment vars, that linking creates.
Please this is not asked anywhere I have checked. Here is what I have done. I am able to deploy single instance of mesos, marathon and docker. Moving next step ahead I want to have 2 mesos slave(docker containers) linked to each other. Just using docker the same can be achieved by using the docker link feature. But while using the orchestration(mesos) and scheduler(marathon)it seems u need to use service discovery.
My setup up is simple and runnning on a single host. So I will have 2 docker containers one running a simple pub/sub and one running rabbitmq. How can I use HA PRoxy in this setup. I have seen some documents provided by mesosphere
http://mesosphere.com/docs/getting-started/service-discovery/ but it is not clear how to go about it.
The canonical approach for service discovery with Mesos + Marathon + Docker is currently what is described in the document you linked.
I'm assuming you're able to get the two applications running in Marathon already.
Typically what happens is:
1) Configure your application definition to include the ports that your application requires.
2) You set up the provided haproxy-marathon-bridge script to run periodically using a utility like cron. This script scrapes Marathon's API to figure out what host and port the application instances are running on and what the known "friendly" port is.
In the example in the service discovery article, the first application has friendly ports of 80 and 443, whilst the second has a friendly port of 8081.
The script then generates a haproxy.cfg configuration that has rules mapping localhost:friendly_port to actual_host:actual_port.
3) Configure your applications to look for each other on localhost:friendly_port. HAProxy will route connections appropriately.
Hope this helps your understanding!
I created a haproxy service discovery docker container that you can run in mesos. It's not production ready but I am using it in my development environment doing exactly what you're trying to do. The reason I prefer this over what comes with marathon is I haven't found a good way to do complicated haproxy configurations with haproxy-marathon-bridge. With spiderweb you can create a template for the haproxy configuration which enables you to do things such as acl routing etc. It doesn't support health checks yet which is something that will need to be done before its production ready. You can see the project here https://github.com/SBRDevelopment/spiderweb.
We have combined Mesos and Marathon with consul and registartor,
so in the end you have haproxy configuration auto-generated with consul-template.
try https://github.com/eBayClassifiedsGroup/PanteraS
All in one container.
With Mesos-DNS you can also do the following:
Setup mesos-dns as in this guide: http://programmableinfrastructure.com/guides/service-discovery/mesos-dns-haproxy-marathon/ (you can skip HAProxy steps they are not required)
When you start your docker containers make sure that they have "namespace %slave_ip_with_mesos_dns%" (replace string with IP address) in their /etc/resolv.conf files.
if lets say name of an app is "peek" it should be reachable from other applications at peek.marathon.mesos