Tutorial: Deploy a multi-container group using a YAML file

Azure Container Instances supports the deployment of multiple containers onto a single host using a container group. A container group is useful when building an application sidecar for logging, monitoring, or any other configuration where a service needs a second attached process.

In this tutorial, you follow steps to run a simple two-container sidecar configuration by deploying a YAML file using the Azure CLI. A YAML file provides a concise format for specifying the instance settings. You learn how to:

  • Configure a YAML file
  • Deploy the container group
  • View the logs of the containers

Note

Multi-container groups are currently restricted to Linux containers.

If you don't have an Azure subscription, create a free account before you begin.

Prerequisites

  • Use Azure Cloud Shell using the Bash environment.

    Launch Cloud Shell in a new window

  • If you prefer, install the Azure CLI to run CLI reference commands.

    • If you're using a local installation, sign in to the Azure CLI by using the az login command. To finish the authentication process, follow the steps displayed in your terminal. For additional sign-in options, see Sign in with the Azure CLI.
    • When you're prompted, install Azure CLI extensions on first use. For more information about extensions, see Use extensions with the Azure CLI.
    • Run az version to find the version and dependent libraries that are installed. To upgrade to the latest version, run az upgrade.

Configure a YAML file

To deploy a multi-container group with the az container create command in the Azure CLI, you must specify the container group configuration in a YAML file. Then pass the YAML file as a parameter to the command.

Start by copying the following YAML into a new file named deploy-aci.yaml. In Azure Cloud Shell, you can use Visual Studio Code to create the file in your working directory:

code deploy-aci.yaml

This YAML file defines a container group named "myContainerGroup" with two containers, a public IP address, and two exposed ports. The containers are deployed from public Microsoft images. The first container in the group runs an internet-facing web application. The second container, the sidecar, periodically makes HTTP requests to the web application running in the first container via the container group's local network.

apiVersion: 2019-12-01
location: eastus
name: myContainerGroup
properties:
  containers:
  - name: aci-tutorial-app
    properties:
      image: mcr.microsoft.com/azuredocs/aci-helloworld:latest
      resources:
        requests:
          cpu: 1
          memoryInGb: 1.5
      ports:
      - port: 80
      - port: 8080
  - name: aci-tutorial-sidecar
    properties:
      image: mcr.microsoft.com/azuredocs/aci-tutorial-sidecar
      resources:
        requests:
          cpu: 1
          memoryInGb: 1.5
  osType: Linux
  ipAddress:
    type: Public
    ports:
    - protocol: tcp
      port: 80
    - protocol: tcp
      port: 8080
tags: {exampleTag: tutorial}
type: Microsoft.ContainerInstance/containerGroups

To use a private container image registry, add the imageRegistryCredentials property to the container group, with values modified for your environment:

  imageRegistryCredentials:
  - server: imageRegistryLoginServer
    username: imageRegistryUsername
    password: imageRegistryPassword

Deploy the container group

Create a resource group with the az group create command:

az group create --name myResourceGroup --location eastus

Deploy the container group with the az container create command, passing the YAML file as an argument:

az container create --resource-group myResourceGroup --file deploy-aci.yaml

Within a few seconds, you should receive an initial response from Azure.

View deployment state

To view the state of the deployment, use the following az container show command:

az container show --resource-group myResourceGroup --name myContainerGroup --output table

If you'd like to view the running application, navigate to its IP address in your browser. For example, the IP is 52.168.26.124 in this example output:

Name              ResourceGroup    Status    Image                                                                                               IP:ports              Network    CPU/Memory       OsType    Location
----------------  ---------------  --------  --------------------------------------------------------------------------------------------------  --------------------  ---------  ---------------  --------  ----------
myContainerGroup  danlep0318r      Running   mcr.microsoft.com/azuredocs/aci-tutorial-sidecar,mcr.microsoft.com/azuredocs/aci-helloworld:latest  20.42.26.114:80,8080  Public     1.0 core/1.5 gb  Linux     eastus

View container logs

View the log output of a container using the az container logs command. The --container-name argument specifies the container from which to pull logs. In this example, the aci-tutorial-app container is specified.

az container logs --resource-group myResourceGroup --name myContainerGroup --container-name aci-tutorial-app

Output:

listening on port 80
::1 - - [02/Jul/2020:23:17:48 +0000] "HEAD / HTTP/1.1" 200 1663 "-" "curl/7.54.0"
::1 - - [02/Jul/2020:23:17:51 +0000] "HEAD / HTTP/1.1" 200 1663 "-" "curl/7.54.0"
::1 - - [02/Jul/2020:23:17:54 +0000] "HEAD / HTTP/1.1" 200 1663 "-" "curl/7.54.0"

To see the logs for the sidecar container, run a similar command specifying the aci-tutorial-sidecar container.

az container logs --resource-group myResourceGroup --name myContainerGroup --container-name aci-tutorial-sidecar

Output:

Every 3s: curl -I http://localhost                          2020-07-02 20:36:41

  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0  1663    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
HTTP/1.1 200 OK
X-Powered-By: Express
Accept-Ranges: bytes
Cache-Control: public, max-age=0
Last-Modified: Wed, 29 Nov 2017 06:40:40 GMT
ETag: W/"67f-16006818640"
Content-Type: text/html; charset=UTF-8
Content-Length: 1663
Date: Thu, 02 Jul 2020 20:36:41 GMT
Connection: keep-alive

As you can see, the sidecar is periodically making an HTTP request to the main web application via the group's local network to ensure that it is running. This sidecar example could be expanded to trigger an alert if it received an HTTP response code other than 200 OK.

Next steps

In this tutorial, you used a YAML file to deploy a multi-container group in Azure Container Instances. You learned how to:

  • Configure a YAML file for a multi-container group
  • Deploy the container group
  • View the logs of the containers

You can also specify a multi-container group using a Resource Manager template. A Resource Manager template can be readily adapted for scenarios when you need to deploy additional Azure service resources with the container group.