# Bitnami Secure Image for Redis&reg; Sentinel

> Redis&reg; Sentinel provides high availability for Redis. Redis Sentinel also provides other collateral tasks such as monitoring, notifications and acts as a configuration provider for clients.

[Overview of Redis&reg; Sentinel](https://redis.io)
Disclaimer: Redis is a registered trademark of Redis Ltd. Any rights therein are reserved to Redis Ltd. Any use by Bitnami is for referential purposes only and does not indicate any sponsorship, endorsement, or affiliation between Redis Ltd.

## TL;DR

```console
docker run --name redis-sentinel -e REDIS_MASTER_HOST=redis bitnami/redis-sentinel: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](https://vmware.github.io/photon/). 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](https://app-catalog.vmware.com/bitnami/apps). Note: Some data is only available with [commercial subscriptions to BSI](https://bitnami.com/).

![Alt text](https://github.com/bitnami/containers/blob/main/BSI%20UI%201.png?raw=true "Application details")
![Alt text](https://github.com/bitnami/containers/blob/main/BSI%20UI%202.png?raw=true "Packaging report")

If you are looking for our previous generation of images based on Debian Linux, please see the [Bitnami Legacy registry](https://hub.docker.com/u/bitnamilegacy).

## 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](https://techdocs.broadcom.com/us/en/vmware-tanzu/application-catalog/tanzu-application-catalog/services/tac-doc/apps-tutorials-work-with-non-root-containers-index.html).

## 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](https://techdocs.broadcom.com/us/en/vmware-tanzu/application-catalog/tanzu-application-catalog/services/tac-doc/apps-tutorials-understand-rolling-tags-containers-index.html).

## Get this image

The Bitnami Redis&reg; Sentinel Docker image is only available to [Bitnami Secure Images](https://bitnami.com) customers.

## Connecting to other containers

Using [Docker container networking](https://docs.docker.com/engine/userguide/networking/), a Redis(R) 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

In this example, we will create a Redis(R) Sentinel instance that will monitor a Redis(R) instance that is running on the same docker network.

#### Step 1: Create a network

```console
docker network create app-tier --driver bridge
```

#### Step 2: Launch the Redis(R) instance

Use the `--network app-tier` argument to the `docker run` command to attach the Redis(R) container to the `app-tier` network.

```console
docker run -d --name redis-server \
    -e ALLOW_EMPTY_PASSWORD=yes \
    --network app-tier \
    bitnami/redis:latest
```

#### Step 3: Launch your Redis(R) Sentinel instance

Finally we create a new container instance to launch the Redis(R) client and connect to the server created in the previous step:

```console
docker run -it --rm \
    -e REDIS_MASTER_HOST=redis-server \
    --network app-tier \
    bitnami/redis-sentinel:latest
```

## Configuration

The following section describes the supported environment variables

### Environment variables

The following tables list the main variables you can set.

#### Customizable environment variables

| Name                                             | Description                                                            | Default Value                         |
|--------------------------------------------------|------------------------------------------------------------------------|---------------------------------------|
| `REDIS_SENTINEL_DATA_DIR`                        | Redis data directory                                                   | `${REDIS_SENTINEL_VOLUME_DIR}/data`   |
| `REDIS_SENTINEL_DISABLE_COMMANDS`                | Commands to disable in Redis                                           | `nil`                                 |
| `REDIS_SENTINEL_DATABASE`                        | Default Redis database                                                 | `redis`                               |
| `REDIS_SENTINEL_AOF_ENABLED`                     | Enable AOF                                                             | `yes`                                 |
| `REDIS_SENTINEL_HOST`                            | Redis Sentinel host                                                    | `nil`                                 |
| `REDIS_SENTINEL_MASTER_NAME`                     | Redis Sentinel master name                                             | `nil`                                 |
| `REDIS_SENTINEL_PORT_NUMBER`                     | Redis Sentinel host port                                               | `$REDIS_SENTINEL_DEFAULT_PORT_NUMBER` |
| `REDIS_SENTINEL_QUORUM`                          | Minimum number of sentinel nodes in order to reach a failover decision | `2`                                   |
| `REDIS_SENTINEL_DOWN_AFTER_MILLISECONDS`         | Time (in milliseconds) to consider a node to be down                   | `60000`                               |
| `REDIS_SENTINEL_FAILOVER_TIMEOUT`                | Specifies the failover timeout (in milliseconds)                       | `180000`                              |
| `REDIS_SENTINEL_MASTER_REBOOT_DOWN_AFTER_PERIOD` | Specifies the timeout (in milliseconds) for rebooting a master         | `0`                                   |
| `REDIS_SENTINEL_RESOLVE_HOSTNAMES`               | Enables hostnames support                                              | `yes`                                 |
| `REDIS_SENTINEL_ANNOUNCE_HOSTNAMES`              | Announce hostnames                                                     | `no`                                  |
| `ALLOW_EMPTY_PASSWORD`                           | Allow password-less access                                             | `no`                                  |
| `REDIS_SENTINEL_PASSWORD`                        | Password for Redis                                                     | `nil`                                 |
| `REDIS_MASTER_USER`                              | Redis master node username                                             | `nil`                                 |
| `REDIS_MASTER_PASSWORD`                          | Redis master node password                                             | `nil`                                 |
| `REDIS_SENTINEL_ANNOUNCE_IP`                     | IP address used to gossip its presence                                 | `nil`                                 |
| `REDIS_SENTINEL_ANNOUNCE_PORT`                   | Port used to gossip its presence                                       | `nil`                                 |
| `REDIS_SENTINEL_TLS_ENABLED`                     | Enable TLS for Redis authentication                                    | `no`                                  |
| `REDIS_SENTINEL_TLS_PORT_NUMBER`                 | Redis TLS port (requires REDIS_SENTINEL_ENABLE_TLS=yes)                | `26379`                               |
| `REDIS_SENTINEL_TLS_CERT_FILE`                   | Redis TLS certificate file                                             | `nil`                                 |
| `REDIS_SENTINEL_TLS_KEY_FILE`                    | Redis TLS key file                                                     | `nil`                                 |
| `REDIS_SENTINEL_TLS_CA_FILE`                     | Redis TLS CA file                                                      | `nil`                                 |
| `REDIS_SENTINEL_TLS_CA_DIR`                      | Directory containing TLS CA certificates                               | `nil`                                 |
| `REDIS_SENTINEL_TLS_DH_PARAMS_FILE`              | Redis TLS DH parameter file                                            | `nil`                                 |
| `REDIS_SENTINEL_TLS_AUTH_CLIENTS`                | Enable Redis TLS client authentication                                 | `yes`                                 |
| `REDIS_MASTER_HOST`                              | Redis master host (used by slaves)                                     | `redis`                               |
| `REDIS_MASTER_PORT_NUMBER`                       | Redis master host port (used by slaves)                                | `6379`                                |
| `REDIS_MASTER_SET`                               | Redis sentinel master set                                              | `mymaster`                            |

#### Read-only environment variables

| Name                                 | Description                           | Value                                          |
|--------------------------------------|---------------------------------------|------------------------------------------------|
| `REDIS_SENTINEL_VOLUME_DIR`          | Persistence base directory            | `/bitnami/redis-sentinel`                      |
| `REDIS_SENTINEL_BASE_DIR`            | Redis installation directory          | `${BITNAMI_ROOT_DIR}/redis-sentinel`           |
| `REDIS_SENTINEL_CONF_DIR`            | Redis configuration directory         | `${REDIS_SENTINEL_BASE_DIR}/etc`               |
| `REDIS_SENTINEL_DEFAULT_CONF_DIR`    | Redis default configuration directory | `${REDIS_SENTINEL_BASE_DIR}/etc.default`       |
| `REDIS_SENTINEL_MOUNTED_CONF_DIR`    | Redis mounted configuration directory | `${REDIS_SENTINEL_BASE_DIR}/mounted-etc`       |
| `REDIS_SENTINEL_CONF_FILE`           | Redis configuration file              | `${REDIS_SENTINEL_CONF_DIR}/sentinel.conf`     |
| `REDIS_SENTINEL_LOG_DIR`             | Redis logs directory                  | `${REDIS_SENTINEL_BASE_DIR}/logs`              |
| `REDIS_SENTINEL_TMP_DIR`             | Redis temporary directory             | `${REDIS_SENTINEL_BASE_DIR}/tmp`               |
| `REDIS_SENTINEL_PID_FILE`            | Redis PID file                        | `${REDIS_SENTINEL_TMP_DIR}/redis-sentinel.pid` |
| `REDIS_SENTINEL_BIN_DIR`             | Redis executables directory           | `${REDIS_SENTINEL_BASE_DIR}/bin`               |
| `REDIS_SENTINEL_DAEMON_USER`         | Redis system user                     | `redis`                                        |
| `REDIS_SENTINEL_DAEMON_GROUP`        | Redis system group                    | `redis`                                        |
| `REDIS_SENTINEL_DEFAULT_PORT_NUMBER` | Redis Sentinel host port              | `26379`                                        |

### Securing Redis(R) Sentinel traffic

Starting with version 6, Redis(R) adds the support for SSL/TLS connections. Should you desire to enable this optional feature, you may use the aforementioned `REDIS_SENTINEL_TLS_*` environment variables to configure the application.

When enabling TLS, conventional standard traffic is disabled by default. However this new feature is not mutually exclusive, which means it is possible to listen to both TLS and non-TLS connection simultaneously. To enable non-TLS traffic, set `REDIS_SENTINEL_PORT_NUMBER` to another port different than `0`.

1. Using `docker run`

    ```console
    $ docker run --name redis-sentinel \
        -v /path/to/certs:/opt/bitnami/redis/certs \
        -v /path/to/redis-sentinel/persistence:/bitnami \
        -e REDIS_MASTER_HOST=redis \
        -e REDIS_SENTINEL_TLS_ENABLED=yes \
        -e REDIS_SENTINEL_TLS_CERT_FILE=/opt/bitnami/redis/certs/redis.crt \
        -e REDIS_SENTINEL_TLS_KEY_FILE=/opt/bitnami/redis/certs/redis.key \
        -e REDIS_SENTINEL_TLS_CA_FILE=/opt/bitnami/redis/certs/redisCA.crt \
        bitnami/redis-cluster:latest
        bitnami/redis-sentinel:latest
    ```

Alternatively, you may also provide with this configuration in your [custom](https://github.com/bitnami/containers/blob/main/bitnami/redis-sentinel#configuration-file) configuration file.

### Configuration file

The image looks for configurations in `/bitnami/redis-sentinel/conf/`. You can mount a volume at `/bitnami` and copy/edit the configurations in the `/path/to/redis-persistence/redis-sentinel/conf/`. The default configurations will be populated to the `conf/` directory if it's empty.

#### Step 1: Run the Redis(R) Sentinel image

Run the Redis(R) Sentinel image, mounting a directory from your host.

```console
docker run --name redis-sentinel \
    -e REDIS_MASTER_HOST=redis \
    -v /path/to/redis-sentinel/persistence:/bitnami \
    bitnami/redis-sentinel:latest
```

#### Step 2: Edit the configuration

Edit the configuration on your host using your favorite editor.

```console
vi /path/to/redis-persistence/redis-sentinel/conf/redis.conf
```

#### Step 3: Restart Redis(R)

After changing the configuration, restart your Redis(R) container for changes to take effect.

```console
docker restart redis
```

Refer to the [Redis(R) configuration](https://redis.iotopics/config) manual for the complete list of configuration options.

### FIPS configuration in Bitnami Secure Images

The Bitnami Redis&reg; Sentinel Docker image from the [Bitnami Secure Images](https://go-vmware.broadcom.com/contact-us) 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 Redis&reg; Sentinel Docker image sends the container logs to the `stdout`. You can configure the containers [logging driver](https://docs.docker.com/engine/admin/logging/overview/) 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

### Starting January 16, 2024

- The `docker-compose.yaml` file has been removed, as it was solely intended for internal testing purposes.

### 4.0.14-debian-9-r201, 4.0.14-ol-7-r222, 5.0.5-debian-9-r169, 5.0.5-ol-7-r175

- Decrease the size of the container. The configuration logic is now based on Bash scripts in the `rootfs/` folder.

### 4.0.10-r25

- The Redis(R) sentinel container has been migrated to a non-root container approach. Previously the container run as `root` user and the redis daemon was started as `redis` user. From now own, both the container and the redis daemon run as user `1001`. As a consequence, the configuration files are writable by the user running the redis process. You can revert this behavior by changing `USER 1001` to `USER root` in the Dockerfile.

## License

Copyright &copy; 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.
