问：安装vCenter服务器的需求是什么？
答：英文很简单，不翻译了。简单注解在下面
值得注意的是最后一段说，SQL Server Express虽然可以用，但是只能用在测试环境或演示用。强烈建议在任何正式环境中都采用商业版本的数据库。
--------------原文分割线--------------------
What are the requirements for a vCenter server?
Your vCenter server should be one of the first things that you set up. As outlined by the Installation and Upgrade Guide, the requirements for setting up vCenter are:
* A physical or virtual machine
* 2 CPU Cores （注意是2个core即可，不是2个CPU）
* 2.0GHz or higher Intel or AMD x86 processor
* 3GB RAM minimum memory （注意，是最少，内存和多少台HOST多少台VM相关，如果是VM，先配4GB吧，以后还可以轻松添加的）
* 2GB disk storage （2GB事实上是不够的，虽然说现在买物理服务器动辄数百GB的硬盘，可以完全不考虑磁盘空间了。但是如果搭建一台VM，则需要特别关注硬盘的空间）
* 10/100 Ethernet adapter minimum, Gigabit is recommended.
For the operating system, you’ll need:
* Windows 2000 SP4, with Update Rollup 1
* Windows XP Pro
* Windows 2003, all releases
* Windows 2008, all releases except Datacenter 64-bit
And finally for the database, you should use:
* Microsoft SQL Server 2005/2008
* Oracle 10g, 11g
SQL Server Express is supported, but realistically, you shouldn’t consider this as an option for anything other than demonstrations or for building a small lab. With the above requirements, a vCenter server can support 20 concurrent clients (people connected via the vSphere Client), 50 ESX Server hosts, and over 250 virtual machines. A quad-processor vCenter server with 8GB RAM can scale to 50 concurrent client connections, 300 ESX Server hosts, and over 3000 virtual machines.
---------------END--------------------------
