How to create a VM from volume snapshot using Horizon dashboard on CREODIAS
In this article, you will learn how to create a virtual machine from a volume snapshot using Horizon dashboard.
Prerequisites
No. 1 Account
You need a CREODIAS hosting account with access to the Horizon interface: https://horizon.cloudferro.com.
No. 2 Familiarity with the process of creating a virtual machine
You need to be familiar with the basics of creating a virtual machine: How to create a Linux VM and access it from Linux command line on CREODIAS
In this article, we work with above mentioned article but modify some of its steps.
No. 3 Volume snapshot created from a bootable volume which contains an operating system
This article involves creating a virtual machine from a volume snapshot. We therefore assume that you already have a volume snapshot created from a bootable volume. See the following articles for more information:
Of course, if you want your new virtual machine to be operational, that bootable volume needs to have a functional operating system, for example Ubuntu 22.04.
In this article, term source volume denotes the volume from which the volume snapshot that we are working with was created.
No. 4 Access to the virtual machine being created
There are different methods of accessing virtual machines. This includes SSH and web console.
For SSH, while creating a virtual machine from a volume snapshot, there is an option of “injecting” an SSH key to the machine being created. Some operating systems are compatible with this feature, while others are not.
If for your particular volume snapshot attaching of an SSH key with this method does not work, make sure that your installation of an operating system includes some method of accessing it.
What We Are Going To Cover
Example scenario in which this article applies
You created an Ubuntu 22.04 virtual machine by following How to create a Linux VM and access it from Linux command line on CREODIAS
While creating that virtual machine, you set option Create New Volume to Yes and option Delete Volume on Instance Delete to No: VM created with option Create New Volume Yes on CREODIAS
After some time, you shut down your virtual machine and deleted it. The volume which was used as boot volume of that VM is still available. You created a snapshot of that volume: How to create or delete volume snapshot on CREODIAS.
Creating VM from volume snapshot using the Horizon dashboard
Step 1: Provide information about virtual machine you want to create
We are modifying steps from reference article How to create a Linux VM and access it from Linux command line on CREODIAS
Changes to Step 2 Boot Source
In Step 2 of above mentioned article, you are supposed to choose the image from which you want to create a virtual machine. Instead of that, from the drop-down menu Select Boot Source choose option Volume Snapshot. This will allow you to choose from the existing volume snapshots.
You should get a list of volume snapshots:
Click ↑ next to the volume snapshot from which you want to create your virtual machine:
It should now be visible in the Allocated section:
You should now be able to proceed to the next step.
Changes to Step 6 SSH key pair
If your particular installation of an operating system supports “injecting” of an SSH key this way, you can perform this step just like it was done in the reference article.
If, however, it is not support this process, make sure that no keys are selected in this step. If a key has already been chosen and exists in the Allocated section, you can click ↓ next to its name to unselect it:
Step 2: Other operations
You should be able to attach a floating IP to a virtual machine created in this way just like to any other virtual machine.
See Step 8 of the reference article.
The floating IP will almost certainly be different from the value given in that article so adjust where needed.
You might also need to configure appropriate security groups: How to use Security Groups in Horizon on CREODIAS
Virtual machines are controlled using different methods, for example SSH or web console. Whatever methods are available on the operating system stored on the volume snapshot should be available on your new virtual machine, since this is the assumption of this article. However, the commands used might be different, for example if the floating IP changed, the SSH command used to access the virtual machine might also change.
What To Do Next
If you want to create a virtual machine from a volume snapshot using the OpenStack CLI client instead of the Horizon dashboard, see: How to create a VM from volume snapshot using OpenStack CLI on CREODIAS
Now that you have created a virtual machine from your volume snapshot, the need may arise in the future to delete that volume snapshot. To that end, see How to create or delete volume snapshot on CREODIAS