According to the World Health Organization, no one knows when avian flu will become transmittable from human to human. The good news is, as CIO/IT managers, we can do something to prepare for it. In case of an outbreak, companies may find that the best way for them to continue to function is to have their employess work at home. With proper technologies, as long as they are connected to the Internet, they can still access the applications (e.g., MS Office, accounting, inventory, custom applications) and files in their offices from their home, just like they were using their office desktop computers.
To allow users to access their applications and files in the office, you can setup Windows Terminal services on a server and install the applications needed onto that server. Then the users can connect to this server over the Internet, login and use it as if they were sitting in front of it. To ensure the data transmission across the Internet is secure, an easy way is to to enable encryption in Windows Terminal services. An even more secure way is to setup a VPN. That's all that is required.
You will need to make sure you have the required number of licenses for the Windows, for Windows Terminal services and for the applications on that server. If it is too expensive to buy extra MS Office licenses, you may install OpenOffice on it instead which costs nothing and works very well with MS Office files.
How many users such a server can support? It is mainly limited by its RAM. For 512M, it may support dozens of users who uses a single application at a time. Only testing will give you more reliable estimates.
Have any questions or ideas regarding how to prepare for the avian
flu?
Contact me at 781313 or kent at cpttm dot org dot mo.
Virtualization means that you can run a software program on a computer and then it will create a virtual computer with its own CPU (using the physical computer's CPU), memory (using the physical computer's RAM), network card (using the physical computer's network card) and hard disk (using a large file in the physical computer). If you run it twice (using another file as the virtual hard disk), you will create another virtual computer. In that virtual computer you can install OS and then applications and they won't notice that it is a virtual computer at all.
You may wonder what is the purpose of that? An important feature is that the models of the virtual devices in the virtual computer are fixed and completely independent of those of the physical computer. For example, even though the physical network card is a 3COM card, the virtual network card may be always an AMD card. The consequence of this is huge: If the physical computer fails (e.g., due to a disk failure), as long as you have a backup copy of that image file, you can just run the virtualization software on a spare computer, start a virtual computer, run the OS and applications in it, then you're back into business. The new virtual computer will be absolutely identical to the original virtual computer. Therefore the OS and the applications won't notice any difference. No need to reinstall OS, reinstall drivers and etc. All this can be done using the free VMware player or the open source Xen.
Some advanced virtualization software even allows you to move a virtual computer from one physical computer to another while it is running! This will be extremely useful if you need to perform a planned maintenance on that physical computer without affecting users (zero downtime).
The possibilitiy doesn't stop here. If you are currently running say Oracle in Windows in one phyiscal computer and Apache in Linux in another physical computer, you can run a virtual computer in the first computer to run Linux and Apache, and run a virtual computer in the second computer to run Windows and Oracle. Given the clustering support in Oracle and Apache, you can setup a 2-node Oracle cluster and a 2-node Apache cluster performing load-balancing or fail-over.
Have any questions, ideas or experiences regarding virtualization? Contact me at 781313 or kent at cpttm dot org dot mo.
Until next time,
Kent Tong