esxi health status displayed in VxRail manager

VxRail in a nutshell

Dell EMC’s VxRail is selling like hotcakes,  I was lucky enough recently to attend a one day overview session on the product.  The training was really good and I wanted to share what I had learnt to present a high level overview on what VxRail is about.

What is VxRail?

VxRail is Dell EMC’s hyper-converged offering. Hyper-converged appliances allow a datacenter in a box approach,  rather than buying servers, storage and hypervisor separately hyper-converged appliances bundle the components into one package.  The storage, compute and hypervisor components used by VXRail are as follows:

  • Storage – VMware vSAN 6.6
  • Compute – 14th Generation DellEMC PowerEdge servers
  • Hypervisor – vSphere 6.5

Together the above form VXRail 4.5

What else do you get with VXRail?

You also get some other software bundled in:

  • vCentre
  • vRealize log insight
  • RecoverPoint for VM’s
  • vSphere Replication
  • vSphere data protection

It is worth noting the ESXi licenses are not included

What is VxRack?

You may also hear VxRack mentioned, this is the bigger brother to VxRail with the software defined storage provided by ScaleIO.  Networking using VMware NSX is also an option.

How many nodes do you need?

The minimum number of nodes required is three,  although 4 is recommended to allow overhead for failures and maintenance.   This is also the minimum number of nodes required to use erasure coding rather than mirroring for data protection.

How do you manage VxRail?

The system is managed from two places.  You will be spending most of your time in the vSphere web console since all vSphere management is still performed from here. Also since the storage is being provided by vSAN this is also managed within vSphere.  The second tool you will need to become familiar with is VxRail Manager.

vSphere Integration

There is the option to create a new vCentre which will be housed within the hyper-converged infrastructure it’s self or to use an external vCentre.  The choice to use an internal or external vCentre can be set during the initial deployment wizard.

What is VxRail Manager?

The VxRail manager allows you to manage the hardware i.e. the servers in a VxRail deployment plus perform a number of other tasks including:

  • Deployment – Initial deployment and addition of nodes
  • Update – As this is a hyper-converged system upgrade of all components can be completed from the VxRail manager.
  • Monitor – Check for events, and monitor resource usage and component status
  • Maintain – Dial home support

The following shows a number of screenshots from within VxRail Manager

Physical node view

vxrail physical health

Logical node view showing resource useage

vxrail logical health

ESXi component status

esxi health status displayed in VxRail manager

What are the models?

You can see detailed specifications of all the models on the DellEMC site, this section just provides the major differences between the series

  • S Series – Hybrid only
  • G Series – Space saving format 2U can contain 4 appliances
  • E Series – 1U hence supports less capacity than the other 2U nodes
  • P Series –  2U supports twice the capacity of E series and is therefore suitable to more demanding workloads
  • V Series – Same spec as P series plus GPU’s. Optimised for VDI environments

How do you add a node

You add a node using the VxRail Manager as shown in the screenshot below which is a non disruptive process. Hybrid and all flash models cannot be mixed plus the first three nodes in any cluster must be identical after this you can mix and match models . Although there is something to be said for maintaining consistency across the cluster so it is balanced and will probably make managing it easier in the future. The cluster can be scaled to a max of 64 nodes.

Adding node to VxRail via VxRail Manager

How do I take a node out for maintenance?

Since the data is stored inside each of the nodes there are some additional considerations when putting a node into maintenance versus using a traditional SAN.  When you do put a host into maintenance mode the default option is ensure accessibility it makes sure all data is available during maintenance, although redundancy may be reduced.

vSAN summary

vSAN is VMware’s software defined storage solution, this means no specialist storage equipment is required and storage is provided by conglomerating the storage within each of the ESXi servers. Key concepts to understand

  • Management  – vSAN is managed from within vSphere and is enabled at the cluster level  
  • Disk groups – Each disk group consists of a caching disk which must be an SSD disk and 1-7 capacity drives.  The capacity drives can be flash drives or spinning disks in a hybrid setup. All writes are made via the caching disk, 30% of its capacity is also reserved to act as a read cache.
  • vSAN datastore – Disk groups are combined together to create a single usable pool of storage called a vSAN datastore
  • Policy Driven – Different performance and availability characteristics can be applied at a per disk level on VMs

vSAN availability and data reduction

  • Dedupe and compression –  Enabled at the cluster level, not suitable for all workloads. If you have a requirement for workloads that do do not require dedupe/compression you would need multiple clusters
  • Availability –
    • Availability and performance levels are set by creating policies, you can have multiple policies on a single vSAN datastore
    • Availability is defined in the policy setting fault tolerance method, the available choices are RAID-1 (Mirroring) and RAID-5/6 (Erasure Coding)
    • RAID 1 is more suited to high performance workloads and will ensure there are two copies of the data across nodes
    • RAID 5 – Stripes the data across nodes, more space efficient but reduced performance.



SFD9 Preview – Will VSAN be THE SAN?

VSAN 6.2

VMware Storage are one of the vendors that will be presenting at Storage Field Day 9, which I will be attending. Given the recent unveiling of VSAN 6.2 it seems very likely this will be the subject matter they will be presenting on. VSAN 6.2 introduced a whole host of much needed features, Duncan Epping summarises them nicely in this post.


One of the key benefits of virtualisation was reducing the number of servers and their foot print in the datacentre. Previous versions of VSAN lacked data reduction technology and RAID 5, requiring that all those servers you moved out following virtualisation would have needed to be wheeled back in again to accommodate capacity.   VSAN 6.2 brought these much needed data reduction features to the table and has arguably for the first time, made VSAN a credible candidate to challenge other hyper-converged and indeed established storage players.

Battle for supremely

What I am especially interested in is VMware’s next tactical play. The key assault from almost all vendors seems to be the battle to own the data centre.

pablo (1)

Rather than selling individual components the aim is to sell packages that meet all the customer’s needs. Nutanix are bidding for more control with their Acropolis OS, EMC have their ever expanding VCE range and HP have their Synergy play to name but a few.

Playing tactically

A key opportunity also exists to bring VSAN into the data centre, not just as part of purpose built hyper-converged appliances but also to the vSphere customers building their own solutions. I wonder if the key to getting VSAN into as many customers’ data centres as possible is by giving away VSAN for free. This is not to devalue VSAN, but if the latest feature set was bundled within vSphere customers would have to ask why wouldn’t we use VSAN?  It may not do everything a high end SAN does, but for most customers it just needs to be good enough.

This may seem like a crazy suggestion but it could give VMware an unassailable lead against not only the software defined solutions but be a major blow against traditional players as well. It would also help to win out in price sensitive deals where Hyper-V is being chosen. VMware would control a good chunk of the data centre and there would be a great amount of inertia to move to another vendor with this level of control.

If this was unpalatable I would still have thought heavy discounting or giving away a quota of free storage space with vSphere coupled with an option to licence further capacity would be the order of the day. Clearly once the brand was established and in data centres everywhere the cost model could be revisited.


Fellow SFD9 delegate Chris M Evans wrote an an interesting article arguing from a different point of view that ESXi should be open sourced. I think this would be a challenge financially, to take away a company’s cash cow and politically to open source the product a company has built its brand on.  Any how I will be interested to hear about VMware’s tactics, about the product, the tech behind it and how they plan to make VSAN be THE SAN at Storage Field Day 9. Remember you can follow along by watching the live stream and have your say by using #SFD9 on Twittter.