vSAN 7.0 U3 feature overview

Duncan Epping · Sep 28, 2021 · 1 Comment

In this blog post, I want to go over the features which have been released for vSAN as part of 7.0 U3. It is not going to be a deep dive, just a simple overview as most features speak for themselves! Let’s list the feature first, and then discuss some of them individually.

• Cluster Shutdown feature
• vLCM support for Witness Appliance
• Skyline Health Correlation
• IO Trip Analyzer
• Nested Fault Domains for 2-Node Clusters
• Enhanced Stretched Cluster durability
• Access Based Enumeration for SMB shares via vSAN File Services

I guess the Cluster Shutdown feature speaks for itself. It basically enables you to power off all the hosts in a cluster when doing maintenance. Even if those hosts contain vCenter Server! If you want to trigger a shutdown, just right click the cluster object, go to vSAN, select “shutdown cluster” and follow the 2-step wizard. Pretty straight forward. Do note, besides the agent VMs, you will need to power-off the other VMs first. (yes, I requested this to be handled by the process as well in the future!)

The Skyline Health Correlation feature is very useful for customers who are seeing multiple alarms being triggered and are not sure what to do. In this scenario, starting with 7.0 U3, vSAN will now understand the correlation between the events and inform you what the issue is (most likely) and show you which other tests it would impact. This should enable you to fix the problem faster than before.

IO Trip Analyzer is also brand new in 7.0 U3. I actually wrote a blog post on the subject separately and included a demo, I would recommend watching that one. But if you just want the short summary, the IO Trip Analyzer basically provides an overview of latency introduced at every layer in the form of a diagram!

Nested Fault Domains for 2-node clusters has been on the “wish list” of some of our customers for a while. It is a very useful feature for those customers who want to be able to tolerate multiple failures even in a 2-node configuration. The feature requires you to have at least 3 disk groups per host, in each of the 2 hosts, and will then enable you to have “RAID-1” across those two hosts and RAID-1 within the host (Or RAID-5/6 if you have sufficient disk groups). If a host fails, and then a disk fails in the surviving host, the VMs would still be available. Basically a feature for customers who don’t need a lot of compute power (3 hosts or more), but do need added resiliency!

Enhanced Stretched Cluster durability (also applies to 2-node) is a feature that Cormac and I requested a while back. We requested this feature as we had heard from a few customers that unfortunately, they had found themselves in a situation where a datacenter would go offline, followed by the witness going down. This would then result in the VMs (only those which were stretched of course) in the remaining location also be unusable, as 2 out of the 3 parts of the RAID tree would be gone. This would even be the case in a situation where you would have a fully available RAID-1 / RAID-5 / RAID-6 tree in the remaining datacenter. This new feature now prevents this scenario!

Last, but not least, we now have support for Access Based Enumeration for SMB shares via vSAN File Services. What does this mean? Pre vSAN 7.0 U3, if a user had access to a file share the user would be able to see all folders/directories in this share. Starting with 7.0 U3 when looking at the share, only the folders that you have the appropriate permissions for will be displayed! (More about ABE here)