This question comes up a lot and only recently did I ask this of engineering and the answer is quite simple. We all know that Preparing a host for vCloud Director essentially installs the vCloud Director Agent onto ESXi. However, the secondary question that usually gets asked is, “What does the vCloud Director Agent actually do?” I decided to ask that and I was also told I could publish the answer. Frankly, the answer is quite simple really.
The vCloud Director Agent is used for two things:
- Communicating with the cross host fencing vmkernel module that is installed when the agent is pushed. This is needed when you use VCD-NI network pools.
- Retrieving virtual machine thumbnails
I was pretty sure I knew about the VCD-NI aspect I just forgot about it. The image thumbnails on the other hand was quite news to me. Either way, now we know what the vCloud Director Agent does once it is installed as part of the host preparation. For information on ways to manually remove the agent see the related posts below.