--- title: 'Docker Swarm' description: "Learn how to manage secrets in Docker Swarm services." --- In this guide, we'll demonstrate how to use Infisical for managing secrets within Docker Swarm. Specifically, we'll set up a sidecar container using the [Infisical Agent](/infisical-agent/overview), which authenticates with Infisical to retrieve secrets and access tokens. These secrets are then stored in a shared volume accessible by other services in your Docker Swarm. ## Prerequisites - Infisical account - Docker version 20.10.24 or newer - Basic knowledge of Docker Swarm - [Git](https://git-scm.com/book/en/v2/Getting-Started-Installing-Git) installed on your system - Familiarity with the [Infisical Agent](/infisical-agent/overview) ## Objective Our goal is to deploy an Nginx instance in your Docker Swarm cluster, configured to display Infisical secrets on its landing page. This will provide hands-on experience in fetching and utilizing secrets from Infisical within Docker Swarm. The principles demonstrated here are also applicable to Docker Compose deployments. Start by cloning the [Infisical guide assets repository](https://github.com/Infisical/infisical-guides.git) from Github. This repository includes necessary assets for this and other Infisical guides. Focus on the `docker-swarm-with-agent` sub-directory, which we'll use as our working directory. To allow the agent to fetch your Infisical secrets, choose an authentication method for the agent. For this guide, we will use [Universal Auth](/documentation/platform/identities/universal-auth) for authentication. Follow the instructions [here](/documentation/platform/identities/universal-auth) to generate a client ID and client secret. Copy the client ID and client secret obtained in the previous step into the `client-id` and `client-secret` text files, respectively. The Infisical Agent will authenticate using Universal Auth and retrieve secrets for rendering as specified in the template(s). Adjust the `polling-interval` to control the frequency of secret updates. In the example template, the secrets are rendered as an HTML page, which will be set as Nginx's home page to demonstrate successful secret retrieval and utilization. Remember to add your project id, environment slug and path of corresponding Infisical project to the secret template. ```yaml infisical-agent-config infisical: address: "https://app.infisical.com" auth: type: "universal-auth" config: client-id: "/run/secrets/infisical-universal-auth-client-id" client-secret: "/run/secrets/infisical-universal-auth-client-secret" remove_client_secret_on_read: false sinks: - type: "file" config: path: "/infisical-secrets/access-token" templates: - source-path: /run/secrets/nginx-home-page-template destination-path: /infisical-secrets/index.html config: polling-interval: 60s ``` Some paths contain `/run/secrets/` because the contents of those files reside in a [Docker secret](https://docs.docker.com/engine/swarm/secrets/#how-docker-manages-secrets). ```html nginx-home-page-template

This file is rendered by Infisical agent template engine

Here are the secrets that have been fetched from Infisical and stored in your volume mount

{{ .Key }}={{ .Value }}

``` Define the `infisical-agent` and `nginx` services in your Docker Compose file. `infisical-agent` will handle secret retrieval and storage. These secrets are stored in a volume, accessible by other services like Nginx. ```yaml docker-compose.yaml version: "3.1" services: infisical-agent: container_name: infisical-agnet image: infisical/cli:0.18.0 command: agent --config=/run/secrets/infisical-agent-config volumes: - infisical-agent:/infisical-secrets secrets: - infisical-universal-auth-client-id - infisical-universal-auth-client-secret - infisical-agent-config - nginx-home-page-template networks: - infisical_network nginx: image: nginx:latest ports: - "80:80" volumes: - infisical-agent:/usr/share/nginx/html networks: - infisical_network volumes: infisical-agent: secrets: infisical-universal-auth-client-id: file: ./client-id infisical-universal-auth-client-secret: file: ./client-secret infisical-agent-config: file: ./infisical-agent-config nginx-home-page-template: file: ./nginx-home-page-template networks: infisical_network: ``` ``` docker swarm init ``` ``` docker stack deploy -c docker-compose.yaml agent-demo ``` To confirm that secrets are properly rendered and accessible, navigate to `http://localhost`. You should see the Infisical secrets displayed on the Nginx landing page. ![Nginx displaying Infisical secrets](/images/docker-swarm-secrets-complete.png) ``` docker stack rm agent-demo ``` ## Considerations - Secret Updates: Applications that access secrets directly from the volume mount will receive updates in real-time, in accordance with the `polling-interval` set in agent config. - In-Memory Secrets: If your application loads secrets into memory, the new secrets will be available to the application on the next deployment.