Minimize download size for offline download in AKS hybrid

In the October release of AKS hybrid, we released offline download, a feature that allows you to pre-download the AKS hybrid images needed for deployment. Offline download enables installing and upgrading at edge locations with unreliable internet connection and allows you to perform security scans on the images before deploying. In the latest release, we have added the option of a minimum or full mode for offline download.

Based on your feedback, we are introducing a minimum and full mode feature to give you the option of minimizing your download size. Minimum mode downloads only the required images, the required Linux images, and the required Kubernetes version needed for an AKS hybrid deployment. Full mode is the default download mode and downloads all the images, including the Windows images. Minimum mode is a great option for you if:

1. Your bandwidth can only accommodate a smaller download size

2. You do not require Windows images i.e. you are only running Linux workloads

3. You do not have a specific Kubernetes version requirement

Check out the table below to see some key differences between the two download modes available. 

*Note: The download time is based on measuring in a test environment with 120 MB download speed. Your time may vary based on available bandwidth and latency. 

Onsite install example steps

The following example will walk you through offline download in minimum mode, assuming that the AKS hybrid prerequisites are satisfied.

1. Check every physical node to see if all the requirements to install are satisfied.

Initialize-AksHciNode

2. Set the configurations to use minimum mode for deployment.

Set-AksHciConfig -offlineDownload $true -mode minimum -stagingShare c:\akshciimages -imageDir c:\clusterstorage\volume1\Images -workingDir c:\ClusterStorage\Volume1\ImageStore -cloudConfigLocation c:\clusterstorage\volume1\Config -vnet $vnet -cloudservicecidr "172.16.10.10/16"

3. (Optional) Check that offline download is enabled and the local path is correct.

Get-AksHciConfig | ConvertTo-Json

4. Log into Azure and configure the registration settings.

Set-AksHciRegistration -subscriptionId <sub_id> -resourceGroupName <resourcegroup_name>

5. Start the deployment.

Install-AksHci

Offsite install example steps

1. Set the offsite configuration.

Set-AksHciOffsiteConfig -version <version>  -stagingShare <staging_share>

2. Download the images in minimum mode.

Get-AksHciRelease -mode minimum

3. Transfer the images onsite to where you will deploy.

4. Set the configurations onsite.

Set-AksHciConfig -offlineDownload $true -offsiteTransferCompleted $true -stagingShare c:\akshciimages -imageDir c:\clusterstorage\volume1\Images -workingDir c:\ClusterStorage\Volume1\ImageStore -cloudConfigLocation c:\clusterstorage\volume1\Config -vnet $vnet -cloudservicecidr "172.16.10.10/16"

5. (Optional) Check that offline download is enabled and the local path is correct.

Get-AksHciConfig | ConvertTo-Json

6. Log into Azure and configure the registration settings.

Set-AksHciRegistration -subscriptionId <sub_id> -resourceGroupName <resourcegroup_name>

7. Start the deployment.

Install-AksHci

You can use minimum mode to upgrade. To learn more about how to use offline download, check out the documentation here. For onsite scenarios, use Set-AksHciConfig to set offline download and use minimum download mode. For offsite scenarios use Set-AksHciOffsiteConfig to set the offsite configuration for offline download and Get-AksHciRelease  to pre-download the images in minimum mode.

Useful links:

Try for free: https://aka.ms/AKS-HCI-Evaluate

Tech Docs: https://aka.ms/AKS-HCI-Docs

Issues and Roadmap: https://github.com/azure/aks-hci

Evaluate on Azure: https://aka.ms/AKS-HCI-EvalOnAzure