10 Must Ask VMware Engineer Interview Questions
VMware Interview Questions
These virtualization engineer interview questions are designed to help determine the level of hands-on experience someone has because it's possible to answer most VMware interview questions normally asked with knowledge gained from a VCP Prep website, VMware for Beginners Guide or even by attending a basic installation and configuration class.
These technical questions are based on scenarios only known, or dealt with, by someone who has been exposed to projects, problems, or issues faced in a real world vSphere environment.
Question #1 (Whiteboard & Marker Required)
Please draw on the whiteboard a high level drawing that details a cluster of 4 ESXi hosts, connected to a vCenter, that has 20 VMs evenly balanced across the hosts. There are 2 network switches (A & B) connected to vSwitches for data and management vLans. The hosts are connected to 4-500GB shared storage LUNs that are presented via fiber channel.
Note: Most qualified virtualization engineers will be able to draw something. If you are recruiting to fill an engineering spot that will be representing your team, it is important that they can whiteboard a high level design with confidence.
Explain the process of P2V and the cleanup process that is required after Windows Servers have been converted from a physical server into a VM.
Answers: Uninstall all no longer required applications for physical hardware, remove hidden devices, and adjust drive sizes, memory and vCPUs. Install VMtools and set screen resolution. Adjust OS swap file.
A new type of SAN storage has been added to the environment to replace the old SAN storage. After presenting the new datastores and migrating the VMs to them, users report slower performance. What could need to be done to the VM file system to fix this?
Answer: Run a block alignment which requires a reboot of the VM (this may not be required on newer operating systems).
You have a cluster of 8 ESXi hosts that require installation of a new security patch that will require a reboot of each host. Explain how you would reboot each host without impacting the VMs.
Answer: Place each host in maintenance mode, which will automatically vMotion the VMs off, then install the patch and reboot the host. Once all is okay and the host is back online, then remove the host from maintenance mode. Repeat the process on the other 7 hosts.
Describe how you would determine when additional ESXi hosts are required? Explain how you determined this?
Answer: By setting thresholds and monitoring host memory and CPU utilization.
How many ESXi hosts have you been responsible for managing in the last 3 years? Ask about the challenges faced.
Answer: More than 30 ESXi hosts is best to provide them with enough hands-on time to experience most of the common issues associated with virtual infrastructures. ESXi Updates, storage, VMtools are common problems.
How many P2Vs have you completed in the last 3 years? Ask about the issues they had.
Answer: More than 25 P2Vs is best because each P2V is unique and develops knowledge of workarounds important for future consolidation projects.
How many VM gold templates have you created? Explain the process you used for resetting any 3rd party applications such as antivirus and backup agents, or any other application which requires a unique key.
Answer: Windows GUIDs are unique IDs that need to be reset or they will be duplicated and cause issues. Also, it is important to sysprep each Windows Server created.
Do you have any experience with cloud automation scripting that leverages Amazon AWS or other cloud computing provider APIs?
Note: Any experience in this area will be beneficial to longer term growth of your environment.
What are your recommendations for backing up VMs? Follow up question, what are your recommendations for monitoring?
Note: These VMware technical interview questions will help you determine what 3rd party applications they are familiar with and allow the candidate to show you if they are passionate about the technology.
If your interviewee can't answer these questions with a conclusive answer then they probably don't have much experience outside basic setup and installation training.
Read more virtualization topics on Joe's vm install blog.
© 2012 Joe Sanchez