8.6 KiB
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.
TL;DR;
docker run --name memcached bitnami/memcached:latest
Docker Compose
$ curl -sSL https://raw.githubusercontent.com/bitnami/bitnami-docker-memcached/master/docker-compose.yml > docker-compose.yml
$ docker-compose up -d
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.
Supported tags and respective Dockerfile links
Subscribe to project updates by watching the bitnami/memcached GitHub repo.
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:
- Please update the YOUR_APPLICATION_IMAGE_ placeholder in the above snippet with your application image
- In your application container, use the hostname
memcached-serverto 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:
- Please update the YOUR_APPLICATION_IMAGE_ placeholder in the above snippet with your application image
- In your application container, use the hostname
memcachedto connect to the Memcached server
Launch the containers using:
$ docker-compose up -d
Configuration
Specify the cache size
By default, the Bitnami Memcached container starts with a cache size of 64mb. You can specify other value using the MEMCACHED_CACHE_SIZE environment variable.
docker run --name memcached -e MEMCACHED_CACHE_SIZE=128 bitnami/memcached:latest
or using Docker Compose:
version: '2'
services:
memcached:
image: 'bitnami/memcached:latest'
ports:
- '11211:11211'
environment:
- MEMCACHED_CACHE_SIZE=128
The default value of the
MEMCACHED_CACHE_SIZEis64.
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_USERNAMEisroot.
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 up memcached
Notable Changes
1.5.0-r1
- The memcached container has been migrated to a non-root container approach. Previously the container run as
rootuser and the memcached daemon was started asmemcacheduser. From now own, both the container and the memcached daemon run as user1001. As a consequence, the configuration files are writable by the user running the memcached process.
1.4.25-r4
MEMCACHED_USERparameter has been renamed toMEMCACHED_USERNAME.
1.4.25-r0
- The logs are always sent to the
stdoutand 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_VERSIONinside the container) - The command you used to run the container, and any relevant output you saw (masking any sensitive information)
License
Copyright (c) 2015-2018 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.