Skip to content

Latest commit

 

History

History
225 lines (186 loc) · 9.92 KB

reliability-containers.md

File metadata and controls

225 lines (186 loc) · 9.92 KB
Raw
title description author ms.author ms.topic ms.custom ms.service ms.date
Reliability in Azure Container Instances
Find out about reliability in Azure Container Instances
anaharris-ms
anaharris
reliability-article
subject-reliability
container-instances
11/29/2022

Reliability in Azure Container Instances

Important

This feature is currently in preview. Previews are made available to you on the condition that you agree to the supplemental terms of use.

This article describes reliability support in Azure Container Instances (ACI) and covers both intra-regional resiliency with availability zones and information on Disaster Recovery. For a more detailed overview of reliability in Azure, see Azure reliability.

Availability zone support

[!INCLUDE Availability zone description]

Azure Container Instances supports zonal container group deployments, meaning the instance is pinned to a specific, self-selected availability zone. The availability zone is specified at the container group level. Containers within a container group can't have unique availability zones. To change your container group's availability zone, you must delete the container group and create another container group with the new availability zone.

Prerequisites

Important

This feature is currently not available for Azure portal.

  • Zonal container group deployments are supported in most regions where ACI is available for Linux and Windows Server 2019 container groups. For details, see Regions and resource availability.
  • If using Azure CLI, ensure version 2.30.0 or later is installed.
  • If using PowerShell, ensure version 2.1.1-preview or later is installed.
  • If using the Java SDK, ensure version 2.9.0 or later is installed.
  • Availability zone support is only available on ACI API version 09-01-2021 or later.

Important

Container groups with GPU resources don't support availability zones at this time.

Availability zone redeployment and migration

To change your container group's availability zone, you must delete the container group and create another container group with the new availability zone.

Create a resource with availability zone enabled

To create a Container Instance resource with availability zone enabled, you'll need to deploy a container group using an Azure Resource Manager (ARM) template.

Note

Examples in this article are formatted for the Bash shell. If you prefer another shell, adjust the line continuation characters accordingly.

To deploy a container with ARM:

  1. Copy-paste the following JSON into a new file named azuredeploy.json. This example template deploys a container group with a single container into availability zone 1 in East US.

    {
    "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
    "contentVersion": "1.0.0.0",
    "metadata": {
        "_generator": {
            "name": "bicep",
            "version": "0.4.1.14562",
            "templateHash": "12367894147709986470"
        }
    },
    "parameters": {
        "name": {
            "type": "string",
            "defaultValue": "acilinuxpublicipcontainergroup",
            "metadata": {
                "description": "Name for the container group"
            }
        },
        "image": {
            "type": "string",
            "defaultValue": "mcr.microsoft.com/azuredocs/aci-helloworld",
            "metadata": {
                "description": "Container image to deploy. Should be of the form repoName/imagename:tag for images stored in public Docker Hub, or a fully qualified URI for other registries. Images from private registries require additional registry credentials."
            }
        },
        "port": {
            "type": "int",
            "defaultValue": 80,
            "metadata": {
                "description": "Port to open on the container and the public IP address."
            }
        },
        "cpuCores": {
            "type": "int",
            "defaultValue": 1,
            "metadata": {
                "description": "The number of CPU cores to allocate to the container."
            }
        },
        "memoryInGb": {
            "type": "int",
            "defaultValue": 2,
            "metadata": {
                "description": "The amount of memory to allocate to the container in gigabytes."
            }
        },
        "restartPolicy": {
            "type": "string",
            "defaultValue": "Always",
            "allowedValues": [
                "Always",
                "Never",
                "OnFailure"
            ],
            "metadata": {
                "description": "The behavior of Azure runtime if container has stopped."
            }
        },
        "location": {
            "type": "string",
            "defaultValue": "eastus",
            "metadata": {
                "description": "Location for all resources."
            }
        }
    },
    "functions": [],
    "resources": [
        {
            "type": "Microsoft.ContainerInstance/containerGroups",
            "apiVersion": "2021-09-01",
            "zones": [
                "1"
            ],
            "name": "[parameters('name')]",
            "location": "[parameters('location')]",
            "properties": {
                "containers": [
                    {
                        "name": "[parameters('name')]",
                        "properties": {
                            "image": "[parameters('image')]",
                            "ports": [
                                {
                                    "port": "[parameters('port')]",
                                    "protocol": "TCP"
                                }
                            ],
                            "resources": {
                                "requests": {
                                    "cpu": "[parameters('cpuCores')]",
                                    "memoryInGB": "[parameters('memoryInGb')]"
                                }
                            }
                        }
                    }
                ],
                "osType": "Linux",
                "restartPolicy": "[parameters('restartPolicy')]",
                "ipAddress": {
                    "type": "Public",
                    "ports": [
                        {
                            "port": "[parameters('port')]",
                            "protocol": "TCP"
                        }
                    ]
                }
            }
        }
    ],
    "outputs": {
        "containerIPv4Address": {
            "type": "string",
            "value": "[reference(resourceId('Microsoft.ContainerInstance/containerGroups', parameters('name'))).ipAddress.ip]"
        }
    }
}

  2. Create a resource group with the [az group create][availability-zones-group-create] command:

    az group create --name myResourceGroup --location eastus

  3. Deploy the template with the az deployment group create command:

    az deployment group create \
  --resource-group myResourceGroup \
  --template-file azuredeploy.json

  4. To verify the container group deployed successfully into an availability zone, view the container group details with the az container show command:

    az containershow --name acilinuxcontainergroup --resource-group myResourceGroup

Zonal failover support

A container group of container instances is assigned to a single availability zone. As a result, that group of container instances won't be impacted by an outage that occurs in any other availability zone of the same region

If, however, an outage occurs in the availability zone of the container group, you can expect downtime for all the container instances within that group.

To avoid container instance downtime, we recommend that you create a minimum of two container groups across two different availability zones in a given region. This ensures that your container instance resources are up and running whenever any single zone in that region experiences outage.

Disaster recovery

When an entire Azure region or datacenter experiences downtime, your mission-critical code needs to continue processing in a different region. Azure Container Instances deployed with zonal configuration run in a specific zone within a specific region. There's no built-in redundancy available. To avoid loss of execution during region wide outages, you can redundantly deploy the container instances in other regions.

Next steps