vSAN 6.7 U3 -What’s New

Following from my last post on vSphere 6.7 U3, this also includes a significant update to vSAN. You know this isn’t just a minor update when there are 2 blog posts to digest on VMware’s blog site.



It’s amazing to see the continued growth of vSAN, now standing at over 20,000 customers running all kinds of workloads form traditional apps from the Microsoft stack to next-gen apps orchestrated suing Kubernetes. It’s certainly hard to keep up with this rapid pace of change we are seeing. 

Intelligent Operations

I’m going to start with the improvements around intelligent operations, especially capacity management. It’s my belief that this is one area that some admins have struggled with. I may be over simplifying this but if you provision a 1TB volume from a storage array, then you know you have 1 TB to use. Looking at a vSAN datastore, the same 1TB would be the RAW capacity, or before any overhead. Also the FTT policy will affect how much usable capacity you actually have to use. It’s great to see the level of detail shown on how capacity is consumed in Update 3. I think this will help admins a lot when it comes to capacity planning. 

The usable capacity analysis feature looks cool – this allows you to choose a storage policy and see how much effective free space is left within the cluster.

Continuing on the operations thread,  there have been some improvements around re syncs. It was possible to cause yourself some pain when performing maintenance in earlier releases. Basically you could already have some form of re sync occurring and it was possible to put a host into maintenance mode which could have had an impact on the availability of the virtual machines. By running pre-checks ahead of any maintenance activity allows admins to make a better informed decisions on whether to proceed. 

Unified Management 

There’s no avoiding it, containers are on the rise. Recent announcements from VMworld saw all kinds of new integrations such as project pacific. With vSAN 6.7U3 there is now tight integration using the Container Storage Interface (CSI) driver for vSphere. This allows admins to mange container based app using persistent volumes as easily as virtual machines. Admins can manage the volume, or first class disk, characteristics to make sure all performance and protection requirements are met. This is all managed using a single UI so everything is simple. 

Enhanced Performance 

There have also been some improvements made around application performance in this release. Data de-staging, which occurs when data moves from cache to capacity tiers, has seen improvements made to give more predictable application performance. This has increased throughput for sequential writes and also means both rebuilds and re sync of data are quicker. With drive capacity increasing all the time this is welcome news. 

The initial release of 6.7 saw Adaptive Resync launched to prioritise IO, update 3 builds on this by allowing parallel reyncs to occur where resources are available. Finally there are new metrics exposed that relate to vSAN CPU utilisation. This can be used in either vRealise Operations or using a vsantop command on each host. These metrics allow the impact of data services such as encryption or deduplication and compression to be measured. 

Enterprise Plus Licensing

There is a new license on the block – this bundles together vSAN Enterprise and vRealise Operations Advanced licenses together giving the following features

  • Stretched Clustering with local protection
  • vSAN Encryption
  • Continuous Performance Optimisation
  • Efficient Capacity Management and Planning
  • Intelligent Remediation