Migrating from vCPU to UHMC additional details on the migration.
What else do I need to know to move from X to Y?
Hello!
I created a couple of articles that cover setting up UMHC licenses and moving from vCPU to Universal Hybrid Multi Cloud (UHMC from now on). In this article I will endeavour to pull this all together. Plus provide some extra commands and information that might be handy specifically related to sizing.
Possibly the first stage is to put new UHMC capacity on your existing NetScaler Console. This ensure that, there is the new capacity to assign from. I talked about the license assignment of UHMC here:
This article used NetScaler Console on-premise, it is very similar to Console Service.
Question: I had a question from Kari about doing something similar where the NetScaler Console was also moving from on-premise Console to NetScaler Console Service. He asked what the order might be for that?
Response: I expect that the best option would be to put the UHMC licenses on the Console Service and migrate Consoles at the same time. This saves moving the licenses twice. Once on to the on-Premise Console and then over to Service..
This next article covers the mechanics of moving the licenses settings from vCPU to UHMC on the NetScaler using the GUI. I will look to create something for a scripted approach, as this would be time consuming for a large estate. Who has time these days?
What else would you need to know? My colleague Nicolas is a details guy! He wanted more specifics, so it makes sense to keep him happy, as he is only asking things that I have not explained completely.
Key items remaining:
What are the steps to move from vCPU to UHMC? This is covered above.
How do I size appliances when I am used to cores?
What do I need to consider in the migration?
Assumptions
You have some access to the NetScaler Console and NetScaler itself, you have super user admin rights. You know the kind of thing, no limits.
In these notes, it will talk about NetScaler Console, this process works for Console Service or on-premise NetScaler Console.
The Steps:
Lets assume that your current estate is running vCPU today.
Install the UHMC licenses once they have access to them on to your NetScaler Console. See the first link above for the specifics.
Follow the steps in the second article to swap the NetScaler appliances over from vCPU to UHMC.
There might need to be some adjustment of the assigned capacity, see the details in the next section to get more on that and the decisions.
Capacity assignment
The previous section made some assumptions about how resources are assigned. The assumption was that what was already assigned would likely be fine in the new licenses approach.
How does vCPU work?
It is really simple, you assign some cores and memory and that is all you need to think about.
How does throughput licensing work?
Throughput requires that you think a bit more about what you are trying to do, then assign some cores, memory and a throughput number.
Where do you start to know how much Throughput is needed? This support doc, has a great table which is below. Keep in mind that the core count in the table actually needs one extra for the management core. This would make a VPX1000 a four core appliance.
Taking the VPX1000 as a baseline, 1Gbps and three cores to process traffic(plus the management core of course) is a good starting point. There are a couple of issues with the table
The table is that this table is for fixed capacity licensing and not any kind of pooled capacity. The different is that, if you add more memory with no more throughput assigned, you will get more cores in your VPX. This could be useful, if you workload is not throttled by bandwidth, core/processing heavy.
The cores need memory to actually spin up, stick to 4G of memory per core as a guide. The lower memory count’s might be a bit optimistic! ‘stat cpu’ and ‘top’ from the shell will give you what you actually have. Remember cores are assigned at boot, so if they are not running when the NetScaler boots, it will need a reboot to get them.
Throughput can be changed dynamically, so if you get the cores and memory roughly right for your workload, you can always dial in a bit more Throughput if needed.
What else is there to consider?
Feature bundle changes: One of the other changes that you might have is that the vCPU bundle is the ‘Advanced’ feature set and UHMC is all ‘Premium’. As there will be a change in licensing there will be a node reboot anyway. When the node is back up, there will be some additional capabilities that you might be keen to look at.
This might also have a influence on the sizing. As if you need the NetScaler to now do some security workloads, such as Web Application Firewall, it might need more resources to service that workload.
Naturally, as UHMC has a large amount of capacity, the additional performance is simple to add.
Summary
Hopefully, this was helpful!