One of the biggest challenges when planning for a Virtual Server deployment is determining the memory requirements for your virtual machines. It is very important that your host computer have adequate memory to support all virtual machines running on it as well as the functions of the host operating system itself.
In order to properly prepare for your deployment you have three things you need to consider. The first of these is the memory requirement for the host operating system. This number is usually not too much as the only function of the host OS is running the virtual server application. The second thing to consider is the amount of memory required for each virtual machine. If you have two machines that each require 512 MB of memory, then you will obviously need 1 GB of RAM to support your virtual machines. Finally, you will need to take into consideration that you must ass 32 MB of memory for each virtual machine you have. This extra memory is required for the processing that takes place between the virtual and physical layers. For instance, if you are running six virtual machines on one host machine you will need to figure for an extra 192 MB of memory. Once you have all these totals figured out you can add everything together and you should be ready to go. As always, it is recommended to add a little extra memory to allow for future growth.
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Chris Sanders is the network administrator for one of the largest public school systems in the state of Kentucky. Chris’s specialties include general network administration, windows server 2003, wireless networking, and security. You can view Chris’ personal website at www.chrissanders.org.
