This information is not new and you may not realise about it. But it come to very handy when problem occur on Hyper V Host.
Once you have install Hyper V Role, you will have additional 10 Event Logs. Check out Custom View > Server Roles > Hyper V.
To explore further, navigate to Applications and Services Log > Microsoft > Windows > Look for Hyper V XXX
Continue expand further to check out 10 Hyper V Event Viewer.
Thanks to Ben, (Original source), here is more detail on each Event Viewer.
This log contains events related to virtual machine Configuration, such as missing VM configuration files.
This log is used for events related to Highly Available virtual machines utilizing Windows Server 2008 Clustering. These events are also replicated to the System log for gathering via Failover Manager.
This log is used by the Hypervisor to record partition creation and deletions.
This log records VHD creations, Image Management Service start events, as well as any action taken with the Edit Disk wizard.
This log is used to record problems associated with the state of Integration Services in Child Partitions.
This log is used to capture the state of virtual networks in the Parent Partition, such as virtual network creation, deletion, or switch port connection.
This log records events related to synthetic network adapters in Child Partitions. For example, if a virtual machine fails to start due to a missing virtual network, the event will be logged here.
This log records events related to synthetic SCSI adapters in Child Partitions.
This log is one of the most commonly used logs for Hyper-V. This contains events related to snapshot merges, Import/Export, the Virtualization WMI Provider, and the state of the virtual machine management service.
This log is also critical in that it contains the state of virtual machines. Events related to Starting/Stopping virtual machines, taking snapshots, as well as the state of emulated and synthetic devices will be logged here.
Hope this give you a first step to assist you further on identify problem.