Identification of advantages should include, but not be limited to

reduced cost in
- capital expenditure
- energy expenditure
- operational expenditure
consolidation of resources
- physical server consolidation
- management of server consolidation
- many applications on each server
- multiple operating systems can exist, isolated from each other, on the same virtual server
isolation
- if one virtual server has a software failure, others are not affected
- upgrades and changes can be made only where required.

Identification of disadvantages should include, but not be limited to

efficiency
- virtual machines are not as efficient in accessing hardware as a real machine
- multiple virtual machines running on a host computer may introduce unstable performance to the host on each virtual machine and thus affect the other virtual machine’s application
cost
- software for virtual machines may cost more due to the expense of virtualization software
- additional software management tools may be required
compatibility (e.g., not all servers and applications are virtualization-friendly)
complex root-cause analysis.