Yellow Bricks

by Duncan Epping

Can I have an AF-4 ReadyNode for vSAN ESA with less memory?

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I got this question the other day, and it was around the amount of memory the AF-4 ReadyNode configuration needs to have in order for it to be supported. I can understand where the question comes from, but what most people don’t seem to understand is that there’s a set of minimal requirements, and that the ReadyNode profiles are as the KB states a “guidance”. The listed configurations are a guidance. This guidance is based on the anticipated resource consumption for a given set of VMs. Of course, this could be very different for your workload. That is why this article that describes the hardware guidance now clearly states the following:

To maintain a configuration supported by VMware Global Services (GS), all ReadyNodes certified for vSAN ESA must meet or exceed the resources of the smallest configuration (vSAN-ESA-AF-0 for vSAN HCI or vSAN-Max-XS for vSAN Max).

This not only applies to memory, but also to other components, as long as you meet the minimum specified below.

Can I have an AF-4 ReadyNode for vSAN ESA with less memory?

Can I disable the vSAN service if the cluster is running production workloads?

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I just had a discussion with someone who had to disable the vSAN service, while the cluster was running a production workload. They had all their VMs running on 3rd party storage, so vSAN was empty, but when they went to the vSAN Configuration UI the “Turn Off” option was grayed out. The reason this option is grayed out is that vSphere HA was enabled. This is usually the case for most customers. (Probably 99.9%.) If you need to turn off vSAN, make sure to temporarily disable vSphere HA first, and of course enable it again after you turned off vSAN! This ensures that HA is reconfigured to use the Management Network instead of the vSAN Network.

Another thing to consider, it could be that you manually configured the “HA Isolation Address” for the vSAN Network, make sure to also change that to an IP address on the Management Network again. Lastly, if there’s still anything stored on vSAN, this will be inaccessible when you disable the vSAN service. Of course, if nothing is running on vSAN, then there will be no impact to the workload.

Can I disable the vSAN service if the cluster is running production workloads?

Unexplored Territory Episode 089 – Discussing the VCP-VVF and VCP-VCF certification with Bart Peeters!

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I’ve seen many folks asking about how difficult the VCP-VCF and VCF-VVF exams are on X and Reddit, so I figured I would invite someone who has actually taken both exams and was even involved in the creation of various VMware exams in the past, and working on the development of an upcoming exam! The podcast is available on all platforms, and of course can be listened to below as well via the embedded player. You can also find the links of the discussed topics here:

vSAN ESA supported with 10GbE networking?

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Somehow I get this question a lot lately, and it seems there’s still some conflicting documentation and messaging out there, is vSAN ESA supported with 10GbE networking or not? The answer is simple, yes it is supported officially. Although you may see some, outdated, blogs and docs state that 25GbE is the minimum, this was actually revised with the introduction of the AF-0 Ready Node configuration for vSAN ESA.

Now, I can fully understand people want this in writing, and after some digging I actually found an update documentation page on the Broadcom website that describes the vSAN ESA and vSAN OSA networking requirements. You can find it here: VMware vSAN – Physical NIC Requirements.

Do files stored on vSAN with vSAN File Services count against the max object count?

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Today I got an interesting question internally: Do files stored on vSAN with vSAN File Services count against the max object count? As I haven’t really discussed this in the past few years, I figured I would do a quick refresher. With vSAN File Services, the files people store on a file share are stored inside a vSAN object. The object itself counts towards the maximum component count you can have in a cluster, but of course the individual files do not.

When it comes to vSAN File Services, for each share you create, you will have to select a policy. The policy will be applied to the object that is created for the file share. Each object, as always, consists of one, or multiple, components. Those components will count towards the maximum number of components a vSAN cluster can have. For a vSAN ESA host the maximum number is 27k components, for vSAN OSA the maximum number of components per host is 9k. Do take into consideration that RAID-1 has a different number of components than RAID-6 for instance, but in general, this should for most customers not be a huge concern unless you have a very large environment (or a small environment and are pushing the boundaries in terms of shares etc).

I hope this helps. PS: The video below shows a demo I gave a few years back in which I inspect these components in the UI and CLI.