CPU Recommendations - ESXi 6.5 & VCSA 6.5

[TrentThomas]

I am looking fo purchase/build a desktop that will have one purpose: run vCenter Server Appliance 6.5 on ESXi 6.5. My environment is very tiny (only 2 other ESXi hosts and less than a dozen or so VMs), and I want to spend as little as possible on parts while still being able to perform necessary VCSA functionality.

I’ve read up on the minimum specification documentation for ESXi 6.5 and vCenter Server Appliance 6.5; however, I would like recommendations on specific parts to ensure what I build is powerful enough to suite my needs, but also as inexpensive as possible.

I know I will be looking at 1 TB storage and 12-16GB of RAM, but I’m mostly curious regarding processor requirements. Documentation recommends 2 vCPUs minimum for a Tiny environment for VSCA, but I want to be 100% certain of my needs before I make a committed purchase. I was thinking maybe any quad core i7 above 2GHz? Or is that more than necessary? Is a hyperthreaded quad core even necessary, or could I get by with an i5? Would it be feasible to go with an older AMD? Basically I know there’s a lot of options for CPUs, and I don’t want to end up buying something that underperforms, but I also don’t want to pay more than necessary to fullfil my needs.

What are your recommendations, and feel free to offer advice on more than just CPU if you desire.

Thanks!

[Deso1ator]

Why do you want one computer running ESXi with only 1 VM, which is the vCSA?

[TrentThomas]

I‘m using vCSA to manage only a few ESXi hosts, and I do not want vCSA to be running on the same ESXi host that is running other important things because it’s bad practice to do so. if you’re not familiar with how, lemme know and I’ll give you examples.

vCenter requires either Windows Server or as a VM (such as on ESXi), and I do not wish to waste a WS license.

I also do not have a scalable server solution so I cannot just simply add a blade to a rack. I had a machine dedicated to this but it failed recently so I’m just looking for an inexpensive replacement.

[IT_pilot]

"I‘m using vCSA to manage only a few ESXi hosts, and I do not want vCSA to be running on the same ESXi host that is running other important things because it’s bad practice to do so. if you’re not familiar with how, lemme know and I’ll give you examples." - yes, I really wanted you to give examples. Given your conviction.

[HassanAlKak88]

Hello,

for compatibility check up, i recommend to use the following:  VMware Compatibility Guide - System Search

Please consider marking this answer "correct" or "helpful" if you think your question have been answered correctly.

Cheers,

VCIX6-NV|VCP-NV|VCP-DC|

@KakHassan

linkedin.com/in/hassanalkak

[Deso1ator]

Why don't you want your vCenter Server running on a host with other VMs? vCenter is no different than other VMs and can run along them with no problems.

The Windows version of vCenter Server will be ending with 6.7. I know you are doing with 6.5, but you will need to eventually go to 6.7 so might as well be ready for it now if you're going with a new install.

Farewell, vCenter Server for Windows - VMware vSphere Blog

[TrentThomas]

IT_pilot

The problem lies in disaster or maintenance management.

Let's go with the following scenario:

ESXi host A

ESXi host B - contains VMs for vCSA, Windows Server 2016, and Windows Server 2012 R2

Since vCSA is being used to manage the ESXi hosts, if host B goes down for some reason, not only do I lose access to that host, but I also lose access to vCenter to manage the hosts and view dashboards and monitoring. This would effectively leave me in the dark regarding all hosts, and if I don't have immediate physical access to the machines, then I'm in a very problematic situation. This is more problematic when vCenter has been configured, for security purposes, to disable remote management of ESXi hosts from anywhere but vCenter. If that was the case, I would be unable to manage any of the other ESXi hosts until I figured out why host B went down and brought it back online. This scenario could happen due to hardware failure or other disaster scenarios. Another issue is if I need to place host B into maintenance mode (as there are a number of scenarios where it is necessary or highly advantageous to place an ESXi host into maintenance mode when changing certain configurations). This requires all VMs to be suspended or shut down first, and that would require vCenter to be suspended or shutdown in the process. This poses similar problems to the disaster situation. I already have encountered similar issues when attempting to manage and configuration an ESXi host from a VM located on that very host.

Now, in a perfect world I would either have redundant vCenter instances on separate hosts (to solve the disaster problem), or I would have high speed migration solutions configured to temporarily move vCenter to another host (to solve the maintenance problem). However, this environment is still very much in infancy and therefore such options are not possible until more money is made available to upgrade to better systems and infrastructure.

By isolating vCenter on a separate device, if any other ESXi hosts go down, I still have access to vCenter to monitor and manage this. If the device hosting vCenter goes down, then sure, I still lose access to vCenter, but at least I know that (unless I'm stricken with terrible luck), the critical VMs are still running on other ESXi hosts, and all I have to focus on is bringing vCenter back online.

HassanAlKak88

That is helpful for checking compatibility. I've found that list isn't comprehensive though, but it's still good info for me to have, thanks. I am still trying to consider which CPU will be powerful enough for vCenter while also be as affordable as possible.

This is the current build I'm considering: https://pcpartpicker.com/user/tethomas/saved/bDYPsY

I know the processor isn't on VMWare's official supported list, but I've read a few threads where people have had success with it. And worst case scenario, if other parts are not by default supported, I'm familiar with how to inject drivers into ESXi installation media.

Deso1ator

Just because you *can* do something, doesn't mean that there aren't consequences for doing so. Please see my answer to IT_pilot. Additionally, as I stated in my previous posts, I am not wanting to waste a Windows Server license on vCenter Server for Windows, and I believe it makes more sense to use vCSA instead, likely for similar reasons that VMWare is using to discontinue vCenter Server for Windows. I'm running vCenter Server Appliance 6.7 and would be running it on ESXi 6.5. Therefore, the deprecation of vCenter for Windows Server does not pose any consequence to me.

[bluefirestorm · Accepted solution]

I am not going to debate the merits of running VCSA 6.5 on a separate ESXi host.

Here are my two cents about any new virtualisation host (be it ESXi, Workstation, Fusion) using older/existing CPUs or second-hand desktops/servers/laptops. I am not familiar with AMD CPUs so maybe there is a bias from me to go with Intel.

In light of Meltdown patch having a performance penalty on network/disk I/O intensive workloads, it is best to go with Intel Haswell CPU generation or newer. This is because Linux-based kernels make use of INVPCID instruction (available on Haswell and newer) to mitigate against that performance penalty. Without INVPCID instruction, any VM (including VCSA) would cause a VMexit if the virtual TLB have to be cleared; that is a performance penalty on VM execution (on top of the Meltdown patch performance penalty on the guest OS). FWIW, I have seen the vmware.log of a Workstation Pro host with AMD FX 8300 and it does not have the INVPCID instruction.

You might be better off purchasing a second-hand business desktop with Haswell CPU (such as Dell Optiplex 9020 or HP EliteDesk 800 G1). You should be able to get one with i5 or i7 Haswell desktop CPU and they come with integrated Intel graphics which frees up the PCIe x16 slot for possible future use for 10Gigabit NIC or dual/quad port Gigabit NIC or some other high-bandwidth I/O card. The business desktop line usually comes with Intel NIC on-board (most likely in the ESXi compatibility list) instead of the consumer lines that come with Realtek (which frees up any slot for future use for other devices).

[TrentThomas]

bluefirestorm

I appreciate the detailed answer; this is what I was looking for. Thank you.