Image pull takes a long time to run

This article discusses what you can do if an image pull takes a long time to run on Microsoft Azure Container Instances.

Prerequisites

• Azure CLI

Symptoms

• Container groups are stuck in a "Created" status for a significant amount of time.

• The image size that's used for the container group is large.

Cause

In Container Instances, images aren't cached forever. If the image isn't cached, the image is pulled from the registry. A registry pull can take a long time if the image is large. This is expected behavior for large, uncached images.

If you need faster pull times, you might want to check whether one of the listed cached images would work successfully for your use case.

Solution

Run the following az container show command so that you can view the timeline of the container events:

az container show --resource-group <resource-group-name> --name <container-group-name>

In this example, the Pulling image event begins at 16:30:51, and the successful Pulled event is recorded on the same day at 16:48:43. Therefore, the image pull takes almost 18 minutes to finish. You can use this information to determine whether the image pull time is expected or abnormal.

{
  "containers": [
    {
      "command": null,
      "environmentVariables": [],
      "image": "pbdockerregistry-on.azurecr.io/software:166884UK",
      "instanceView": {
        "currentState": {
          "detailStatus": "",
          "exitCode": null,
          "finishTime": null,
          "startTime": "2019-01-22T16:49:11+00:00",
          "state": "Running"
        },
        "events": [
          {
            "count": 1,
            "firstTimestamp": "2019-01-22T16:30:51+00:00",
            "lastTimestamp": "2019-01-22T16:30:51+00:00",
            "message": "pulling image \"pbdockerregistry-on.azurecr.io/software:166884UK\"",
            "name": "Pulling",
            "type": "Normal"
          },
          {
            "count": 1,
            "firstTimestamp": "2019-01-22T16:48:43+00:00",
            "lastTimestamp": "2019-01-22T16:48:43+00:00",
            "message": "Successfully pulled image \"pbdockerregistry-on.azurecr.io/software:166884UK\"",
            "name": "Pulled",
            "type": "Normal"
          },
          {
            "count": 1,
            "firstTimestamp": "2019-01-22T16:48:43+00:00",
            "lastTimestamp": "2019-01-22T16:48:43+00:00",
            "message": "Created container with docker id 2dfc27ee4e6",
            "name": "Created",
            "type": "Normal"
          },
          {
            "count": 1,
            "firstTimestamp": "2019-01-22T16:49:11+00:00",
            "lastTimestamp": "2019-01-22T16:49:11+00:00",
            "message": "Started container with docker id 2edfc27ee4e6",
            "name": "Started",
            "type": "Normal"
          }
        ],
        "previousState": null,
        "restartCount": 0
      },
      "livenessProbe": null,
      "name": "<container-name>",
      "ports": [
        {
          "port": 443,
          "protocol": "TCP"
        }
      ],
      "readinessProbe": null,
      "resources": {
        "limits": null,
        "requests": {
          "cpu": 4.0,
          "memoryInGb": 4.0
        }
      },
      "volumeMounts": null
    }
  ],
  "diagnostics": null,
  "id": "/subscriptions/<subscription-id>/resourceGroups/<resource-group-name>/providers/Microsoft.ContainerInstance/containerGroups/<container-name>",
  "identity": null,
  "imageRegistryCredentials": [
    {
      "password": null,
      "server": "<user-name>.azurecr.io",
      "username": "<user-name>"
    }
  ],
  "instanceView": {
    "events": [],
    "state": "Running"
  },
  "ipAddress": {
    "dnsNameLabel": "<container-name>",
    "fqdn": "<container-name>.westeurope.azurecontainer.io",
    "ip": "40.119.152.151",
    "ports": [
      {
        "port": 443,
        "protocol": "TCP"
      }
    ],
    "type": "Public"
  },
  "location": "westeurope",
  "name": "<container-name>",
  "networkProfile": null,
  "osType": "Windows",
  "provisioningState": "Succeeded",
  "resourceGroup": "<resource-group-name>",
  "restartPolicy": "Always",
  "tags": {},
  "type": "Microsoft.ContainerInstance/containerGroups",
  "volumes": null
}

More information

• Azure Container Apps image pull with managed identity

Contact us for help

If you have questions or need help, create a support request, or ask Azure community support. You can also submit product feedback to Azure feedback community.