Hi, thanks for the query. Virtual machines will be classified as unknown in OME, this is working as expected as OME is meant for managing and monitoring Dell hardware. For switches, 1. Are these Dell switches? If yes, which models? 2. Which protocol are you using to discover them? If SNMP, have you configured SNMP protocol on the switch for proper discovery?
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Switch & Virtual machine showing health status to unknown & unable to move in 
servers tabs, please find attached image & help & support to resolved issue.