Microsoft Exchange on Nutanix Best Practice Guide

I am pleased to announce that the Best Practice guide for Microsoft Exchange on Nutanix is released and can be found here.

For me deploying MS Exchange on Nutanix with vSphere combines best of breed application level resiliency (in the form of Exchange Database Availability Groups), infrastructure and hypervisor technologies to provide an infrastructure with not only high performance, but with industry leading scalability, no silos and very high efficiency & resiliency.

All of this leads to overall lower CAPEX/OPEX for customers.

In summary by Virtualizing MS Exchange on Nutanix, customers realize several key benefits including:

  • Ability to use a standard platform for all workloads in the datacenter, thus allowing the removal of legacy silos resulting in lower overall cost, and increased operational efficiencies.
    • An example of this is no disruption to MS Exchange users when performing Nutanix / Hypervisor or HW maintenance
  • A highly resilient , scalable and flexible MS Exchange deployment.
  • Reducing the number of Exchange Mailbox servers required to maintain 4 copies of Exchange data thanks to the combination of NDFS + DAG. (2 copies at NDFS layer / 2 copies at DAG layer)
  • Eliminate the need for large / costly refresh cycles of HW as individual nodes can be added and removed non disruptively.
  • Simplified architecture, no need for complex sizing architecture or risk of over sizing day 1, start small and scale VMs, Compute or storage if/when required.
  • No dependency of specific HW, Exchange VMs can be migrated to/from any Nutanix node and even to non Nutanix nodes.
  • Full support from Nutanix including at the Exchange, Hypervisor and Storage layers with support from Microsoft via Premier Support contracts or via TSANet.
  • Lower CAPEX/OPEX as Exchange can be combined with new or existing Nutanix/Virtualization deployment.
  • Reduced datacenter costs including Power, Cooling , Space (RU)

I hope you enjoy the Best Practice guide and look forward to hearing about your MS Exchange on Nutanix questions & experiences.

Enterprise Architecture & Avoiding tunnel vision.

Recently I have read a number of articles and had several conversations with architects and engineers across various specialities in the industry and I’m finding there is a growing trend of SMEs (Subject Matter Experts) having tunnel vision when it comes to architecting solutions for their customers.

What I mean by “Tunnel Vision” is that the architect only looks at what is right in front of him/her (e.g.: The current task/project) , and does not consider the implications of how the decisions being made for this task may impact the wider I.T infrastructure and customer from a commercial / operational perspective.

In my previous role I saw this all to often, and it was frustrating to know the solutions being designed and delivered to the customers were in some cases quite well designed when considered in isolation, but when taking into account the “Big Picture” (or what I would describe as the customers overall requirements) the solutions were adding unnecessary complexity, adding risk and increasing costs, when new solutions should be doing the exact opposite.

Lets start with an example;

Customer “ACME” need an enterprise messaging solution and have chosen Microsoft Exchange 2013 and have a requirement that there be no single points of failure in the environment.

Customer engages an Exchange SME who looks at the requirements for Exchange, he then points to a vendor best practice or reference architecture document and says “We’ll deploy Exchange on physical hardware, with JBOD & no shared storage and use Exchange Database Availability Groups for HA.”

The SME then attempts to justify his recommendation with “because its Microsoft’s Best practice” which most people still seem to blindly accept, but this is a story for another post.

In fairness to the SME, in isolation the decision/recommendation meets the customers messaging requirements, so what’s the problem?

If the customers had no existing I.T and the messaging system was going to be the only I.T infrastructure and they had no plans to run any other workloads, I would say the solution proposed could be a excellent solution, but how many customers only run messaging? In my experience, none.

So lets consider the customer has an existing Virtual environment, running Test/Dev, Production and Business Critical applications and adheres to a “Virtual First” policy.

The customer has already invested in virtualization & some form of shared storage (SAN/NAS/Web Scale) and has operational procedures and expertises in supporting and maintaining this environment.

If we were to add a new “silo” of physical servers, there are many disadvantages to the customer including but not limited too;

1. Additional operational documentation for new Physical environment.

2. New Backup & Disaster Recovery strategy / documentation.

3. Additional complexity managing / supporting a new Silo of infrastructure.

4. Reduced flexibility / scalability with physical servers vs virtual machines.

5. Increased downtime and/or impact in the event hardware failures.

6. Increased CAPEX due to having to size for future requirements due to scaling challenges with physical servers.

So what am I getting at?

The cost of deploying the MS Exchange solution on physical hardware could potentially be cheaper (CAPEX) Day 1 than virtualizing the new workload on the existing infrastructure (which likely needs to be scaled e.g.: Disk Shelves / Nodes) BUT would likely result overall higher TCO (Total Cost of Ownership) due to increased complexity & operational costs due to the creation of a new silo of resources.

Both a physical or virtual solution would likely meet/exceed the customers basic requirement to serve MS Exchange, but may have vastly different results in terms of the big picture.

Another example would be a customer has a legacy SAN which needs to be replaced and is causing issues for a large portion of the customers workloads, but the project being proposed is only to address the new Enterprise messaging requirements. In my opinion a good architect should consider the big picture and try to identify where projects can be combined (or a projects scope increased) to ensure a more cost effective yet better overall result for the customer.

If the architect only looked at Exchange and went Physical Servers w/ JBOD, there is zero chance of improvement for the rest of the infrastructure and the physical equipment for Exchange would likely be oversized and underutilized.

It will in many cases be much more economical to combine two or more projects, to enable the purchase of a new technology or infrastructure components and consolidate the workloads onto shared infrastructure rather than building two or more silo’s which add complexity to the environment, and will likely result in underutilized infrastructure and a solution which is inferior to what could have been achieved by combining the projects.

In conclusion, I hope that after reading this article, the next time you or your customers embark on a new project, that you as the Architect, Project Manager, or Engineer consider the big picture and not just the new requirement and ensure your customer/s get the best technical and business outcomes and avoid where possible the use of silos.

What does Exchange running in a VMDK on NFS datastore look like to the Guest OS?

In response to the recent community post “Support for Exchange Databases running within VMDKs on NFS datastores” , the co-authors and I have received lots of feedback, of which the vast majority has been constructive and positive.

Of the feedback received which does not fall into the categories of constructive and positive, it appears to me as if this is as a result of the issue is not being properly understood for whatever reason/s.

So in an attempt to help clear up the issue, I will show exactly what the community post is talking about, with regards to running Exchange in a VMDK on an NFS datastore.

1. Exchange nor the Guest OS is not exposed in any way to the NFS protocol

Lets make this very clear, Windows or Exchange has NOTHING to do with NFS.

The configuration being proposed to be supported is as follows

1. A vSphere Virtual Machine with a Virtual SCSI Controller

In the below screen shot from my test lab, the highlighted SCSI Controller 0 is one of 4 virtual SCSI controllers assigned to this Virtual machine. While there are other types of virtual controllers which should also be supported, Paravirtual is in my opinion the most suitable for an application such as Exchange due to its high performance and low latency.

ExchangeVMSCSIController

2. A Virtual SCSI disk is presented to the vSphere Virtual Machine via a Virtual SCSI Controller

The below shows a Virtual disk (or VMDK) presented to the Virtual machine. This is a SCSI device (ie: Block Storage – which is what Exchange requires)

Note: The below shows the Virtual Disk as “Thin Provisioned” but this could also be “Thick Provisioned” although this has minimal to no performance benefit with modern storage solutions.

ExchangeVMVMDK

So now that we have covered what the underlying Virtual machine looks like, lets see what this presents to a Windows 2008 guest OS.

In Computer Management, under Device Manager we can see the expanded “Storage Controllers” section showing 4 “VMware PVSCSI Controllers”.

ExchangeVMPVSCSIController

Next, still In Computer Management, under Device Manager we can see the expanded “Disk Drives” section showing a number of “VMware Virtual disk SCSI Disk Devices” which each represent a VMDK.

 

 

ExchangeVMDeviceManager

 

 

 

 

Next we open “My Computer” to see how the VMDKs appear.

As you can see below, the VMDKs appear as normal drive letters to Windows.

ExchangeVMMyComputer

 

Lets dive down further, In “Server manager” we can see each of the VMDKs showing as an NTFS file system, again a Block storage device.

ExchangeVMDiskManager

Looking into one of the Drives, in this case, Drive F:\, we can see the Jetstress *.EDB file is sitting inside the NTFS file system which as shown in the “Properties” window is detected as a “Local disk”.

ExchangeVMFdriveProperties

So, we have a Virtual SCSI Controller, Virtual SCSI Disk, appearing to Windows as a local SCSI device formatted with NTFS.

So what’s the issue? Well as the community post explains, and this post shows, there isn’t one! This configuration should be supported!

The Guest OS and Exchange has access to block storage which meets all the requirements outlined my Microsoft, but for some reason, the fact the VMDK sits on a NFS datastore (shown below) people (including Microsoft it seems) mistakenly assume that Exchange is being serviced by NFS which it is NOT!

ExchangeVMDatastore

 

I hope this helps clear up what the community is asking for, and if anyone has any questions on the above please let me know and I will clarify.

Related Articles

1. “Support for Exchange Databases running within VMDKs on NFS datastores

2. Microsoft Exchange Improvements Suggestions Forum – Exchange on NFS/SMB