containers/bitnami/memcached

Bitnami Secure Image for 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

Use this quick command to run the container.

docker run --name memcached bitnami/memcached:latest

Why use Bitnami Secure Images?

Those are hardened, minimal CVE images built and maintained by Bitnami. Bitnami Secure Images are based on the cloud-optimized, security-hardened enterprise OS Photon Linux. Why choose BSI images?

• Hardened secure images of popular open source software with Near-Zero Vulnerabilities
• Vulnerability Triage & Prioritization with VEX Statements, KEV and EPSS Scores
• Compliance focus with FIPS, STIG, and air-gap options, including secure bill of materials (SBOM)
• Software supply chain provenance attestation through in-toto
• First class support for the internet’s favorite Helm charts

Each image comes with valuable security metadata. You can view the metadata in our public catalog here. Note: Some data is only available with commercial subscriptions to BSI.

If you are looking for our previous generation of images based on Debian Linux, please see the Bitnami Legacy registry.

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.

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 .

Using docker-compose.yaml

Please be aware this file has not undergone internal testing. Consequently, we advise its use exclusively for development or testing purposes. For production-ready deployments, we highly recommend utilizing its associated Bitnami Helm chart.

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 host name.

Configuration

The following sections describe environment variables and related settings.

Environment variables

The following tables list the main variables you can set.

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).

Specify maximum number of concurrent connections

By default, the Bitnami Memcached container will not specify any maximum number of concurrent connections and will start with Memcached defaults (1024 concurrent connections). You can specify a different value with the MEMCACHED_MAX_CONNECTIONS environment variable.

Specify number of threads to process requests

By default, the Bitnami Memcached container will not specify the amount of threads for which to process requests for and will start with Memcached defaults (4 threads). You can specify a different value with the MEMCACHED_THREADS environment variable.

Specify max item size (slab size)

By default, the Memcached container will not specify any max item size and will start with Memcached defaults (1048576 ~ 1 megabyte). You can specify a different value with the MEMCACHED_MAX_ITEM_SIZE environment variable. Only numeric values are accepted - use 8388608 instead of 8m

Creating the Memcached admin user

Authentication on the Memcached server is disabled by default. To enable authentication, specify the password for the Memcached admin user using the MEMCACHED_PASSWORD environment variable (or in the content of the file specified in MEMCACHED_PASSWORD_FILE).

To customize the username of the Memcached admin user, which defaults to root, the MEMCACHED_USERNAME variable should be specified.

Note

The default value of the MEMCACHED_USERNAME is root.

Passing extra command-line flags to memcached

Passing extra command-line flags to the Memcached service command is possible by adding them as arguments to run.sh script:

docker run --name memcached bitnami/memcached:latest /opt/bitnami/scripts/memcached/run.sh -vvv

Alternatively, modify the docker-compose.yml file present in this repository:

services:
  memcached:
  ...
    command: /opt/bitnami/scripts/memcached/run.sh -vvv
  ...

Refer to the Memcached man page for the complete list of arguments.

Using custom SASL configuration

In order to load your own SASL configuration file, you will have to make them available to the container. You can do it doing the following:

• Mounting a volume with your custom configuration
• Adding custom configuration via environment variable.

By default, when authentication is enabled the SASL configuration of Memcached is written to /opt/bitnami/memcached/sasl2/memcached.conf file with the following content:

mech_list: plain
sasldb_path: /opt/bitnami/memcached/conf/memcachedsasldb

The /opt/bitnami/memcached/conf/memcachedsasldb is the path to the sasldb file that contains the list of Memcached users.

FIPS configuration in Bitnami Secure Images

The Bitnami Memcached Docker image from the Bitnami Secure Images catalog includes extra features and settings to configure the container with FIPS capabilities. You can configure the next environment variables:

• OPENSSL_FIPS: whether OpenSSL runs in FIPS mode or not. yes (default), no.

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.

Notable changes

The following subsections describe notable changes.

1.5.18-debian-9-r13 and 1.5.19-ol-7-r1

• Fixes regression in Memcached Authentication introduced in release 1.5.18-debian-9-r6 and 1.5.18-ol-7-r7 (#62).

1.5.18-debian-9-r6 and 1.5.18-ol-7-r7

• Decrease the size of the container. The configuration logic is now based on Bash scripts in the rootfs/ folder.
• Custom SASL configuration should be mounted at /opt/bitnami/memcached/conf/sasl2/ instead of /bitnami/memcached/conf/.
• Password for Memcached admin user can be specified in the content of the file specified in MEMCACHED_PASSWORD_FILE.

1.5.0-r1

• The Memcached container has been migrated to a non-root container approach. Previously the container run as root user and the Memcached daemon was started as memcached user. From now on, both the container and the Memcached daemon run as user 1001. As a consequence, the user running the Memcached process can write to the configuration files.

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.

License

Copyright © 2026 Broadcom. The term "Broadcom" refers to Broadcom Inc. and/or its subsidiaries.

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.