bitnami-containers/bitnami/memcached/README.md

What is Memcached?

Memcached is an in-memory key-value store for small chunks of arbitrary data (strings, objects) from results of database calls, API calls, or page rendering.

memcached.org

TL;DR;

docker run --name memcached bitnami/memcached:latest

Docker Compose

version: '2'

services:
  memcached:
    image: 'bitnami/memcached:latest'
    ports:
      - '11211:11211'

Kubernetes

WARNING: This is a beta configuration, currently unsupported.

Get the raw URL pointing to the kubernetes.yml manifest and use kubectl to create the resources on your Kubernetes cluster like so:

$ kubectl create -f https://raw.githubusercontent.com/bitnami/bitnami-docker-memcached/master/kubernetes.yml

Why use Bitnami Images?

• Bitnami closely tracks upstream source changes and promptly publishes new versions of this image using our automated systems.
• With Bitnami images the latest bug fixes and features are available as soon as possible.
• Bitnami containers, virtual machines and cloud images use the same components and configuration approach - making it easy to switch between formats based on your project needs.
• Bitnami images are built on CircleCI and automatically pushed to the Docker Hub.
• All our images are based on minideb a minimalist Debian based container image which gives you a small base container image and the familiarity of a leading linux distribution.

Get this image

The recommended way to get the Bitnami Memcached Docker Image is to pull the prebuilt image from the Docker Hub Registry.

docker pull bitnami/memcached:latest

To use a specific version, you can pull a versioned tag. You can view the list of available versions in the Docker Hub Registry.

docker pull bitnami/memcached:[TAG]

If you wish, you can also build the image yourself.

docker build -t bitnami/memcached:latest https://github.com/bitnami/bitnami-docker-memcached.git

Connecting to other containers

Using Docker container networking, a Memcached server running inside a container can easily be accessed by your application containers.

Containers attached to the same network can communicate with each other using the container name as the hostname.

Using the Command Line

Step 1: Create a network

$ docker network create app-tier --driver bridge

Step 2: Launch the Memcached server instance

Use the --network app-tier argument to the docker run command to attach the Memcached container to the app-tier network.

$ docker run -d --name memcached-server \
    --network app-tier \
    bitnami/memcached:latest

Step 3: Launch your application container

$ docker run -d --name myapp \
    --network app-tier \
    YOUR_APPLICATION_IMAGE

IMPORTANT:

1. Please update the YOUR_APPLICATION_IMAGE_ placeholder in the above snippet with your application image
2. In your application container, use the hostname memcached-server to connect to the Memcached server

Using Docker Compose

When not specified, Docker Compose automatically sets up a new network and attaches all deployed services to that network. However, we will explicitly define a new bridge network named app-tier. In this example we assume that you want to connect to the Memcached server from your own custom application image which is identified in the following snippet by the service name myapp.

version: '2'

networks:
  app-tier:
    driver: bridge

services:
  memcached:
    image: 'bitnami/memcached:latest'
    networks:
      - app-tier
  myapp:
    image: 'YOUR_APPLICATION_IMAGE'
    networks:
      - app-tier

IMPORTANT:

1. Please update the YOUR_APPLICATION_IMAGE_ placeholder in the above snippet with your application image
2. In your application container, use the hostname memcached to connect to the Memcached server

Launch the containers using:

$ docker-compose up -d

Configuration

Creating the Memcached admin user

Authentication on the Memcached server is disabled by default. To enable authentication, specify a username and password for the Memcached admin user using the MEMCACHED_USERNAME and MEMCACHED_PASSWORD environment variables.

docker run --name memcached \
  -e MEMCACHED_USERNAME=my_user \
  -e MEMCACHED_PASSWORD=my_password \
  bitnami/memcached:latest

or using Docker Compose:

version: '2'

services:
  memcached:
    image: 'bitnami/memcached:latest'
    ports:
      - '11211:11211'
    environment:
      - MEMCACHED_USERNAME=my_user
      - MEMCACHED_PASSWORD=my_password

The default value of the MEMCACHED_USERNAME is root.

Logging

The Bitnami Memcached Docker image sends the container logs to the stdout. To view the logs:

docker logs memcached

or using Docker Compose:

docker-compose logs memcached

You can configure the containers logging driver using the --log-driver option if you wish to consume the container logs differently. In the default configuration docker uses the json-file driver.

Maintenance

Upgrade this image

Bitnami provides up-to-date versions of Memcached, including security patches, soon after they are made upstream. We recommend that you follow these steps to upgrade your container.

Step 1: Get the updated image

docker pull bitnami/memcached:latest

or if you're using Docker Compose, update the value of the image property to bitnami/memcached:latest.

Step 2: Remove the currently running container

docker rm -v memcached

or using Docker Compose:

docker-compose rm -v memcached

Step 3: Run the new image

Re-create your container from the new image.

docker run --name memcached bitnami/memcached:latest

or using Docker Compose:

docker-compose start memcached

Notable Changes

1.4.25-r4

• MEMCACHED_USER parameter has been renamed to MEMCACHED_USERNAME.

1.4.25-r0

• The logs are always sent to the stdout and are no longer collected in the volume.

Contributing

We'd love for you to contribute to this container. You can request new features by creating an issue, or submit a pull request with your contribution.

Issues

If you encountered a problem running this container, you can file an issue. For us to provide better support, be sure to include the following information in your issue:

• Host OS and version
• Docker version (docker version)
• Output of docker info
• Version of this container (echo $BITNAMI_IMAGE_VERSION inside the container)
• The command you used to run the container, and any relevant output you saw (masking any sensitive information)

Community

Most real time communication happens in the #containers channel at bitnami-oss.slack.com; you can sign up at slack.oss.bitnami.com.

Discussions are archived at bitnami-oss.slackarchive.io.

License

Copyright (c) 2015-2016 Bitnami

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.