The cons of VMWare?

pwjohnston

With the prevalent use of virtualization in the marketplace and it's proven worth I find it difficult to understand why some still doubt it. Still I think it's always good to know your weaknesses and I have been looking at VMWare since it's the big one. Most times the only con I hear against VMWare is the price. Now while that can be a big con I don't always hear many other issues. Sometimes someone brings up the memory ballooning issue, but I'm trying to dig a little deeper here.

So I'm curious what you guys think. Outside of the cost issue and memory balloning issue, what are the application specific cons of using VMware, in an SMB server deployment, as opposed to all the other virtualization options?

RTmarc

Price is the only thing I've ever encountered.

Complexity would be another item of concern but that's not specifically VMware. Most people want the full functionality of virtualization without giving much thought to the underlying requirements; e.g., SAN / centralized storage, etc. Again, that's not VMware specific, but rather virtualization as a whole.

Claymoore

Well, there was that one day when everything went horribly wrong:
All Your VMs Are Belong to Us

Vendor support is another issue. For example, Microsoft supports virtualizing most of their products, even on VMWare. However, they may ask you to attempt to reproduce a problem on physical hardware if they are assisting you in troubleshooting one of their products on a VMWare virtual server. MS can't get some of the troubleshooting information they need due to how VMWare virtualizes the hardware - although they can get this information from Hyper-V. Certain products, such as Exchange, also have different support requirements. MS does not support combining VM HA with Exchange HA, so you can have VMotion or DAGs but not both.

Hyper-V and Xen Server have their own issues, but there are challenges that are common across the hypervisors. Some products, particularly anything with high I/O rates, don't virtualize well. Anything that hogs all the resources will starve the other VMs, so that you may only have a couple of guests on one host and that decreases the cost benefit of virtualization. Then there are products that require specialized hardware that can't be virtualized at all. Finally there is the inevitable server sprawl that results from having 'free' virtual servers. Spare capacity is quickly eaten up and now you have to manage and patch all those new servers.

JDMurray

The lack of standardization across all of VMware's software apps is very noticeable and degrades the usability of their products. One would hope a single committee of people is overseeing the uniformity of appearance and operation of all VMware products, but it doesn't seem so. And after reading a few employment reviews about VMware, it looks like their product development might be very compartmentalized (that is, VMware's internal product development groups don't talk to each other).