How to resize a Windows guest vm disk in ESX Part I: VMware Converter

A couple of days ago one of my customers asked me if it was possible to increase the size of the C partition on one of his Windows 2003 servers. He did not size that vm's (and a few others, as it turned out) disk large enough and was running out of space.

There are a few ways to resize a Windows vm disk. In this post, I am going to look at how it  is done with VMware Converter. In another post I will tackle a more advanced/challenging method without Converter. Let's take a look:

In order to use the VMware Converter, I would select my vm in the Virtual Center Inventory and choose the "export" option:

Let's try making the disk smaller first:

In this example, I changed the size of the disk from 6 GB to 5 GB.

Upon completion of the Export wizard, the Converter goes off to build the new disk:

Once the new vm is created, I boot it up and the disk reflects the new size:

I can also use Converter to increase the size of my disk:

After the machine is exported, the new disk reflects the bigger size:

NOTE: As readily observable, export/import with decreasing the disk size takes roughly 3 times longer then increasing the size of the disk. The reason being that if you do not change the disk size or increase it, then it does a block level clone of the drive. If you reduce the size of your original disks it instead does a file level clone of the drive (much slower).