FIGHT! The VMware vs. Hyper-V Debate Continues
Year over year, the debate continues. Even after I write this blog post, the debate will continue. VMware vs. Hyper-V. The truth is that both hypervisors have their advantages and disadvantages. To start with, let’s take a look at the prominent ones.
- Thin hypervisor with a tiny install that can be run on a SD card.
- FAST live migration (vMotion). This allows you to perform maintenance operations faster, without downtime.
- Memory isolation. This is critical to prevent VM memory errors from crashing the hypervisor and vice versa.
- Streamlined automatic dynamic memory management and transparent page sharing allowing for better consolidation ratios — to the tune +25–50% more VMs per host. It is important to note that Hyper-V does support dynamic memory management with manual configuration when all the VMs and hypervisor are on the same patch level.
- No downtime needed to clone a VM.
- Storage IO Control (SIOC) which is necessary to optimize storage access to VMs!
- Dynamic serial and parallel ports.
- Virtual Volumes & VSAN!
- Direct driver capabilities which allow for a shorter IO path and better overall VM performance.
- Overall better Linux, Unix, and Mac guest level support.
- Anti-Virus offload. This is critical for VDI based deployments and helps to reduce/eliminate AV impacts to underlying disk; though we will see how this shakes out with NSX.
- Overall Hot Add/Remove support for memory, NICs, CPUs, and disks.
- Unified web based management through vCenter.
- Native storage support for ODX at the hypervisor level by default.
- Network bandwidth, capping, and reservations are more flexible than Network IO Control.
- Native clustering without central management system like vCenter.
- Native HA without central management system like vCenter.
- Native live migration without central management system like vCenter.
Really, what we have are two hypervisors that are fairly equal in basic day to day feature sets if you don’t care about consolidation ratios, high performance, and can suffer downtime to perform a large majority of management tasks — with Hyper-V. So, if you can survive that… Cost.
- Hyper-V is free! This is the one major thing that I ALWAYS hear from Hyper-V fans. But is it really? Hyper-V is included as part of the Windows OS — great. Let’s not forget that VMware provides ESXi for free as well. Granted, with the free ESXi hypervisor, you won’t have the native cluster, HA, or Live Migration. Also, with VMware, you do get better consolidation ratios, so you will save on the overall hardware costs since you can potentially fit more VMs on a single host. This may not be a great thing on a single server, but if you can fit 5 Hyper-V server’s worth of VMs on a three node cluster of ESXi servers — the low cost that you pay for a base vSphere Essentials license is more than covered for in the hardware savings alone.
- The Hyper-V management interface for a Hyper-V cluster consists of a disparate set of tools. You need to use Failover Cluster Manager, Hyper-V Manager, and other tools just to perform basic administration tasks. Even with SCVMM — which you will pay $10K+ for, you still can’t do full centralized management. In a VMware environment, if I want to clone a template and spin up a VM — I am talking less than 5 minutes by clicking a wizard and assigning the customization template. With Hyper-V I have to go through a myriad of steps that waste 20 minutes of time. If I have to deploy 10 machines, that is no longer 50 minutes as it might be with VMware — but a total of 200 minutes with Hyper-V. Take that across all the disconnected management tasks required and you are talking an operational cost increase of around 300% in man hours PLUS a 300% increase in maintenance windows potentially which will impact mission critical business functions.
I suppose if all you care about is the CAPEX cost and don’t really care about on-going OPEX costs, extended outage windows, and really feel like adding additional servers to handle your VM load while increasing power and cooling costs — well then Hyper-V is free. VMware is not cheap, and admittedly you do have to pay for add-ons, up to a point. Also, with VMware, the cost is upfront and renewed for support w/upgrade rights yearly (same for Hyper-V on the support if you want it). If all you need is the basics, they both work. If you know Hyper-V and feel like scripting PowerShell for automation, then it is quite capable. But don’t ever tell me it is free. Remember you mother probably told that there is nothing in this world for free — so why should you think Hyper-V is?
Now, I am not saying Hyper-V is bad. But I would not use it for mission critical applications where my job depended on it. Not yet anyway. There may come a day. For now, it is relegated to the lab.