VM Template #

This guide will show how kthcloud manages VM templates and ensures that the templates are available in every zone.

We host every template separately from CloudStack, as CloudStack integrate such a system better (cross-zone template synchronization by URL). This is hosted as a Jail in TrueNAS in the Flemingsberg zone. It is exposed on IP http://172.31.5.12 only accessible internally (through a VPN).

You can also view and edit the template files as a NFS storage at kthcloud Drive.

Customize the template #

Start by customizing a VM that you want to use as a template. This include installing the necessary packages, creating users etc.

Normally this is done by customizing the VM called “Ubuntu 22.04 Cloud template”.

Ensure the VM is Stopped when you are done.

If using “Ubuntu 22.04 Cloud template”, make sure to run “prepare-template.sh” before turning it off.

Prepare the download #

Navigate to VM that you want to template, and find the root disk.

Click “Download Volume”. This will not actually download the volume, but prepare it for download and then give you a link.

Copy the link.

Download the template in the Template server #

To ensure that all templates are synchronized in the zone, we host templates separately from CloudStack, since CloudStack integrates such as system better.

Login at https://nas.cloud.cbh.kth.se and navigate to “Jails” and enter the shell for the jail called “templates”.

Run cd /opt/templates then wget <cloudstack link> -O <template name>

Add the template to CloudStack #

Go to https://dashboard.cloud.cbh.kth.se and navigate to “Images/Templates”.

Click “Register template from URL” an enter the information (KVM, QCOW2 image). Use the IP 172.31.5.12 to reference the template server.

Ensure the template is synchronized to every Zone.

Once the template is registered, ensure it is downloaded in every Zone.