Vmware ESX presents far more benefits than it does problems, it is reliable and scalable from a small group of test servers through to a live trading stock exchange back end.
Most of the percieved virtualisation limitations are in fact generique system limitations imposed elsewhere, however VMWare is not perfect because nothing is.
For one, its expensive and the price scales as the size of your deployment does, licencing can quickly run into 10's or 100's of $ a year for a even a modest 3 or 4 host ESX cluster, especially as the most interesting services and features are licenced as extras.
e.g. High Availability and Distributed Resource Scheduler ( HA+DRS ), VMWare Consilidated Backup (VCB)
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This article was written by a VMWare Certified Professional, whilst rolling out VMWare yourself is possible and encouraged, it could also be costly if things go wrong.
Consider employing a VMWare certified consultant to assist you if you are planning for your business production enviroment unless you are 100% sure what you are doing ! It will save you time, money and stress because certified professionals are qualified and know what to look for when it comes to planning, as well as knowing the best practices and tricks they earned their stripes with.
