A lot of times we rip through a new Windows VM install without too much thought. What actually occurs during this process? When using the new VM wizard, we are creating parameters for a VM, which go into a database that is the heart of XenServer. Once the wizard completes, during the OS install phase, the Windows installation runs fully virtualized. So, if we assign 4 virtual CPUs, and 8GBs of RAM, how does this affect our XenServer environment? Until the XenTools are installed in a Windows VM, it is running fully virtualized with all the work being done by the domain 0 controlling VM (AKA “dom 0”).
If you are in a heavy environment (multiple XenServers in a pool or multiple VMs on a XenServer), do we really want to place all of this extra work on dom 0? Sure it can be done, by why bother? For me, it is much faster to rip through the defaults for VM name, CPU, and RAM until I get to the storage section, whci is the only customization I do. The network interfaces can be automatically assigned via the properties of the Network tab of the XenServer. If you have a dedicated NIC for VMs, that should be the only one you see.
So, now we have the OS installed. What next? I prefer to install the XenTools at this point so I don’t have issues with a static IP address later. If we have a static IP address now, then install the XenTools later, the current interface will still be present, but hidden as it is inactive. Windows will inform you of an IP address conflict. So at this point, proceed with the XenTools installation without configuring a static IP first. Real important
Once the XenTools are installed, this is when I assign the number of CPUs, amount of RAM, and then proceed with the configuration of any static IP addresses (unless if this VM will be used as a custom template). With me so far? Great. So now we have a paravirtualized VM we can then make sure we have all applicable hot fixes applied via Windows Update.
At this point, we are pretty much done. Only thing left is to install applications and perform standard Windows System Administration.