How many licenses will a move to vSphere 5 require?-revisited!
In a previous blog post, we explored how to create a Virtualization Manager dashboard that tracked the total vRAM pool, host CPU sockets and the number of vSphere 5 licenses required for each edition based on VMware’s recently announced vSphere 5.
Last week (presumably based on customer feedback), VMware announced a slight change to vSphere 5 licensing. Specifically, VMware has increased the memory (vRAM) entitlements for each vSphere edition, as well as cap the vRAM at 96GB for VMs configured with more memory than that. (haven’t seen too many VMs larger than 96GB in my travels but I guess they’re out there somewhere 
)
Let’s compare the initial vSphere 5 licensing with the update recently announced.
Ok – it looks like we’ll need to update our dashboard in 2 main areas.
- We need to make sure the total vRAM calculation caps VMs at 96GB for those configured with more than that amount
- We need to use the new memory entitlement values to calculate the number of vSphere licenses required
Our old vRAM pool calculation was pretty simple, it simply added up the total configured memory across all Powered ON VMs. We need to change the logic slightly to choose the minimum of the configured memory and 96GB (i.e. VMs with more than 96GB get capped at 96GB) The updated vRAM trend now performs this logic (remember that Virtualization Manager stores configured memory in MB so we need to convert it to GB, i.e. 96GB is 98304MB)
Finally, we need to adjust the license count trends. Let’s take a look at the Enterprise Plus case.
So we take the new vRAM calculation (with 96GB cap) and divide by 96GB instead of 48GB to reflect the new memory entitlement for Enterprise Plus edition.
Let’s take a look at the results – we’ve left the old calculation on the dashboard so it can be compared to the new.
First thing you notice is that our vRAM pool hasn’t changed- we don’t have any VMs with more than 96GB of configured RAM in this environment Subsequently, the number of vSphere 5 licenses needed in this environment falls in line with the equivalent increase in memory entitlements (e.g. the number of enterprise plus licenses needed drops in half, since the memory entitlement doubled for this edition)
Download the updated dashboard and let us know what you think.