Question 1
What are you running today?
Everything that follows adapts to this answer. If you run more than one platform, choose the one carrying most of the workload. XenServer, XCP-ng, OLVM, OpenShift Virtualization and anything else are covered by Something else, or mixed.
Question 2
Roughly how many VMs would move to the new platform?
Not everything you run - the machines you would actually migrate. A ballpark is fine. It sets the floor for everything else.
Question 3
Total memory allocated to the VMs moving
Allocated, not used. That difference is bigger than most people expect - we will show you why.
Assumed at 14.6 GB each - our own cluster's average, not a typical machine. Change it if you know yours.
Your own figure - we will not overwrite it.
Question 4
Total virtual CPUs allocated
Again allocated, not used - across all the VMs moving.
Assumed at 4.3 each, same cluster. Change it if you know yours.
Your own figure - we will not overwrite it.
Question 5
Storage actually in use
What the VMs consume, not what the array holds.
Assumed at 0.56 TB each, same cluster. Change it if you know yours.
Your own figure - we will not overwrite it.
Question 6
When does your current agreement end?
This changes the advice more than any technical answer.
The environment round
Five questions about what surrounds your machines
The machines themselves migrate. These are the things that get rebuilt, re-licensed or replaced - and this is where the work and the cost actually sit.
Question 7
-
Question 8
-
Question 9
What backs it up?
Question 10
What do you monitor with?
Question 11
Any of these in the estate?
Tap all that apply. These need handling separately, and it is better to know now.
An indicative shape - not a sizing
Modelled on our own migration off VMware, not on an industry average.
What is driving it
-
-
Everything below is how we got there - open whichever sections you would like more detail on.
Processor - the one we will not pretend to size
-
-
The thing nobody mentions
The target platform does not overcommit memory by default
-
-
One worked alternative
If you right-sized first
-
What you would be licensed on
-
-
Raw is not usable
-
-
Your rebuild list
Things that do not move across
For each one: what does the job on the new platform, what the move actually involves, and what changes once you are living with it.
The management plane
-
-
What we have NOT counted
Things that will add to this, and we would rather say so
- A separate management cluster. Once you are running more than one tenant, or at any real scale, leading practice puts the management plane on its own cluster with its own resilience floor. That is nodes on top of the number above, and whether you need one is a design decision rather than a calculation.
- Backup infrastructure. The new platform has no equivalent of the transport your current product uses, so it deploys worker machines onto the cluster itself - which consume the cores you are licensed for.
- The migration tooling. A small appliance, and only for the duration, but it has to live somewhere while it runs.
- The controller's own footprint on disk. We have deducted its memory and accounted for its processor, but its system and metadata space on the drives is inside our working headroom rather than counted separately.
- Anything you stand up new - file services, database services, monitoring you have to replace, a test cluster.
What we could not see
Being straight with you
-
If you do one thing
-
-
Your reference -

