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Bitnami Secure Image for Memcached

What is Memcached?

Memcached is an high-performance, distributed memory object caching system, generic in nature, but intended for use in speeding up dynamic web applications by alleviating database load.

Overview of Memcached Trademarks: This software listing is packaged by Bitnami. The respective trademarks mentioned in the offering are owned by the respective companies, and use of them does not imply any affiliation or endorsement.

TL;DR

docker run --name memcached bitnami/memcached:latest

⚠️ Important Notice: Upcoming changes to the Bitnami Catalog

Beginning August 28th, 2025, Bitnami will evolve its public catalog to offer a curated set of hardened, security-focused images under the new Bitnami Secure Images initiative. As part of this transition:

Granting community users access for the first time to security-optimized versions of popular container images.
Bitnami will begin deprecating support for non-hardened, Debian-based software images in its free tier and will gradually remove non-latest tags from the public catalog. As a result, community users will have access to a reduced number of hardened images. These images are published only under the “latest” tag and are intended for development purposes
Starting August 28th, over two weeks, all existing container images, including older or versioned tags (e.g., 2.50.0, 10.6), will be migrated from the public catalog (docker.io/bitnami) to the “Bitnami Legacy” repository (docker.io/bitnamilegacy), where they will no longer receive updates.
For production workloads and long-term support, users are encouraged to adopt Bitnami Secure Images, which include hardened containers, smaller attack surfaces, CVE transparency (via VEX/KEV), SBOMs, and enterprise support.

These changes aim to improve the security posture of all Bitnami users by promoting best practices for software supply chain integrity and up-to-date deployments. For more details, visit the Bitnami Secure Images announcement.

Why use Bitnami Secure Images?

Bitnami Secure Images and Helm charts are built to make open source more secure and enterprise ready.
Triage security vulnerabilities faster, with transparency into CVE risks using industry standard Vulnerability Exploitability Exchange (VEX), KEV, and EPSS scores.
Our hardened images use a minimal OS (Photon Linux), which reduces the attack surface while maintaining extensibility through the use of an industry standard package format.
Stay more secure and compliant with continuously built images updated within hours of upstream patches.
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.
Hardened images come with attestation signatures (Notation), SBOMs, virus scan reports and other metadata produced in an SLSA-3 compliant software factory.

Only a subset of BSI applications are available for free. Looking to access the entire catalog of applications as well as enterprise support? Try the commercial edition of Bitnami Secure Images today.

How to deploy Memcached in Kubernetes?

Deploying Bitnami applications as Helm Charts is the easiest way to get started with our applications on Kubernetes. Read more about the installation in the Bitnami Memcached Chart GitHub repository.

Why use a non-root container?

Non-root container images add an extra layer of security and are generally recommended for production environments. However, because they run as a non-root user, privileged tasks are typically off-limits. Learn more about non-root containers in our docs.

Supported tags and respective `Dockerfile` links

Learn more about the Bitnami tagging policy and the difference between rolling tags and immutable tags in our documentation page.

You can see the equivalence between the different tags by taking a look at the tags-info.yaml file present in the branch folder, i.e bitnami/ASSET/BRANCH/DISTRO/tags-info.yaml.

Subscribe to project updates by watching the bitnami/containers 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 by cloning the repository, changing to the directory containing the Dockerfile and executing the docker build command. Remember to replace the APP, VERSION and OPERATING-SYSTEM path placeholders in the example command below with the correct values.

git clone https://github.com/bitnami/containers.git
cd bitnami/APP/VERSION/OPERATING-SYSTEM
docker build -t bitnami/APP:latest .

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-server to connect to the Memcached server

Using a Docker Compose file

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 memcached to connect to the Memcached server

Launch the containers using:

docker-compose up -d

Configuration

Environment variables

Customizable environment variables

Name	Description	Default Value
`MEMCACHED_LISTEN_ADDRESS`	Host that the Memcached service will bind to.	`nil`
`MEMCACHED_PORT_NUMBER`	Port number used by Memcached.	`11211`
`MEMCACHED_USERNAME`	Memcached admin username.	`root`
`MEMCACHED_PASSWORD`	Password for the Memcached admin user.	`nil`
`MEMCACHED_MAX_ITEM_SIZE`	Memcached maximum item size.	`nil`
`MEMCACHED_EXTRA_FLAGS`	Extra flags to be used when running Memcached.	`nil`
`MEMCACHED_MAX_TIMEOUT`	Maximum timeout in seconds for Memcached to start or stop.	`5`
`MEMCACHED_CACHE_SIZE`	Memcached cache size in MB.	`nil`
`MEMCACHED_MAX_CONNECTIONS`	Maximum amount of concurrent connections that Memcached will tolerate.	`nil`
`MEMCACHED_THREADS`	Amount of process threads that Memcached will use.	`nil`

Read-only environment variables

Name	Description	Value
`MEMCACHED_BASE_DIR`	Memcached installation directory.	`${BITNAMI_ROOT_DIR}/memcached`
`MEMCACHED_CONF_DIR`	Memcached configuration directory.	`${MEMCACHED_BASE_DIR}/conf`
`MEMCACHED_DEFAULT_CONF_DIR`	Memcached configuration directory.	`${MEMCACHED_BASE_DIR}/conf.default`
`MEMCACHED_BIN_DIR`	Memcached directory for binary executables.	`${MEMCACHED_BASE_DIR}/bin`
`SASL_CONF_PATH`	Memcached SASL configuration directory.	`${MEMCACHED_CONF_DIR}/sasl2`
`SASL_CONF_FILE`	Memcached SASL configuration	`${SASL_CONF_PATH}/memcached.conf`
`SASL_DB_FILE`	Memcached SASL database file.	`${SASL_CONF_PATH}/memcachedsasldb`
`MEMCACHED_DAEMON_USER`	Memcached system user.	`memcached`
`MEMCACHED_DAEMON_GROUP`	Memcached system group.	`memcached`

Specify the cache size

By default, the Bitnami Memcached container will not specify any cache size and will start with Memcached defaults (64MB). You can specify a different value with the MEMCACHED_CACHE_SIZE environment variable (in MB).

docker run --name memcached -e MEMCACHED_CACHE_SIZE=128 bitnami/memcached:latest