Digitalocean Install Docker
This article is the tutorial on how to install playSMS, a Free and Open Source SMS portal or SMS gateway, using Docker in DigitalOcean. We will be using the Docker application image available on DigitalOcean and playSMS Docker image available in Docker hub. The tutorial can be followed in about 30 minutes. Once you learnt then you can do this again faster, I’d say less than 15 minutes. Login to DigitalOcean.
Introduction is a great tool, but to really take full advantage of its potential it's best if each component of your application runs in its own container. For complex applications with a lot of components, orchestrating all the containers to start up and shut down together (not to mention talk to each other) can quickly become unwieldy. The Docker community came up with a popular solution called, which allowed you to use a single YAML file to orchestrate all your Docker containers and configurations. This became so popular that the Docker team eventually decided to make their own version based on the Fig source. Hp deskjet 6122 alternate driver. They called it Docker Compose.
In short, it makes dealing with the orchestration processes of Docker containers (such as starting up, shutting down, and setting up intra-container linking and volumes) really easy. By the end of this article, you will have Docker and Docker Compose installed and have a basic understanding of how Docker Compose works. Docker and Docker Compose Concepts Using Docker Compose requires a combination of a bunch of different Docker concepts in one, so before we get started let's take a minute to review the various concepts involved.
If you're already familiar with Docker concepts like volumes, links, and port forwarding then you might want to go ahead and skip on to the next section. Docker Images Each Docker container is a local instance of a Docker image. You can think of a Docker image as a complete Linux installation. Usually a minimal installation contains only the bare minimum of packages needed to run the image. These images use the kernel of the host system, but since they are running inside a Docker container and only see their own file system, it's perfectly possible to run a distribution like CentOS on an Ubuntu host (or vice-versa).
Most Docker images are distributed via the, which is maintained by the Docker team. Most popular open source projects have a corresponding image uploaded to the Docker Registry, which you can use to deploy the software.
When possible it's best to grab 'official' images, since they are guaranteed by the Docker team to follow Docker best practices. Communication Between Docker Images Docker containers are isolated from the host machine by default, meaning that by default the host machine has no access to the file system inside the Docker container, nor any means of communicating with it via the network. Needless to say, this makes configuring and working with the image running inside a Docker container difficult by default. Docker has three primary ways to work around this. The first and most common is to have Docker specify environment variables that will be set inside the Docker container.
The code running inside the Docker container will then check the values of these environment variables on startup and use them to configure itself properly. Another commonly used method is a. Docker volumes come in two flavors — internal and shared. Specifying an internal volume just means that for a folder you specify for a particular Docker container, the data will be persisted when the container is removed. For example if you wanted to make sure your log files hung around you might specify an internal /var/log volume. A shared volume maps a folder inside a Docker container onto a folder on the host machine. This allows you to easily share files between the Docker container and the host machine, which we'll explore in the.