How do I use Docker on cloud or datacenter

I have run docker on AWS and other cloud providers. It is really not that hard if you have some experience with system administration and or devops. Regarding cloud hosters and getting started, most providers have some sort of tutorial on how to get started using docker with their infrastructure:

• http://docs.aws.amazon.com/AmazonECS/latest/developerguide/docker-basics.html
• https://azure.microsoft.com/en-us/documentation/articles/virtual-machines-linux-dockerextension/

Can I build a docker image with any type of server (eg. wildfly, payara) and/or database server (eg. mysql, oracle) and will it work on docker enabled cloud/datacenter?

To get a server up and running, you just need the docker engine installed on the host, there are packages for many distros:

• https://docs.docker.com/engine/installation/

After docker engine is installed, you can create dockerfiles for basically any server or service. Hopefully you do not need to, in most cases, since there are countless docker files and pre-configured, vendor maintained images already available on dockerhub (I use wildfly, elk-stack, and mysql for example). Be careful about selecting images are maintained, otherwise you end up with security issues in your images that might never get fixed! Or you have to do it yourself!

Example images:

• https://hub.docker.com/r/jboss/wildfly/
• https://hub.docker.com/_/mysql/
• https://hub.docker.com/_/oraclelinux/
• https://hub.docker.com/u/payara/

If it's yes how about persistent datas like database files and static storages (eg. images, uploaded documents, logs) those are stored in docker images or somewhere else? What will happen to those files when I update my application and redeploy new image?

In general, you will want to store persistent data external to the docker image and mount it into the image as a volume:https://docs.docker.com/engine/tutorials/dockervolumes/

Some cloud based storage providers might be easier to mount or connect to in other ways, but this volume approach is standard, IMO.

For logfiles, I actually push them to an ELK server, so having a volume for the logs is not necessarily required. However, since the ELK server is also a docker image, it does have a volume where the data is persisted.

So you have:

• documentation from your cloud hoster (or docker themselves)
• a host in your cloud running docker engine
• 0..n images that you can either grab from dockerhub or build yourself.
• storage for persistent data on this host or mounted from elsewhere that you mount into your docker images on startup. this is where e.g. mysql data folders live, or where you can persist logs, etc.

Of course, it can get much more complex from there, e.g. how to transparently scale and update your environment etc., but that is something for e.g. kubernetes or docker swarm or some other solution (I've scripted a bit on my own but do not need the robustness or elastic scalability of large systems).

Regarding cluster management, it should be noted that Swarm is now included in the Docker Core. This has created some controversy in the community and even talks of a fork of the core:

• https://technologyconversations.com/2015/11/04/docker-clustering-tools-compared-kubernetes-vs-docker-swarm/
• https://jaxenter.com/docker-1-12-is-probably-the-most-important-release-since-1-0-129080.html
• http://searchitoperations.techtarget.com/news/450303918/Docker-fork-talk-prompts-container-standardization-brawl
• http://www.infoworld.com/article/3118345/cloud-computing/why-kubernetes-is-winning-the-container-war.html

I have experience running docker on Alibaba cloud and AWS as well. I did not see any difference in working with docker on both cloud providers. Docker images can be build same way on all linux platform regardless of the cloud provider. However, persistence of data need to be taken care using docker volumes. However, it is recommended to use managed service such as RDS in Alibaba cloud for databases instead of using docker.

Can I build a docker image with any type of server (eg. wildfly, payara) and/or database server (eg. mysql, oracle) and will it work on docker enabled cloud/datacenter?

You can build your own Docker images or use solutions that are already pre-packaged and proven by cloud providers. For example, here is an auto-clustering Docker-based implementation of GlassFish that can be run and managed on Jelastic PaaS.

If it's yes how about persistent datas like database files and static storages (eg. images, uploaded documents, logs) those are stored in docker images or somewhere else? What will happen to those files when I update my application and redeploy new image?

With the above mentioned cluster, all data is kept inside containers and stays without changes after restart. As an option, you can also connect a separate data storage container if you wish to share it across other containers.