3.5.4.5.1.2 RODC server cachability validation
If the NTLMv2_CLIENT_CHALLENGE request (see [MS-NLMP] section 2.2.2.7) does not include a non-empty MsvAvNbComputerName AVPair (see [MS-NLMP] section 2.2.2.1), the validation succeeds.
Otherwise, validation proceeds as follows:
Let NBComputerName be the value of the MsvAvNbComputerName AVPair.
Append a ‘$’ character to NBComputerName.
Let RODC be the Read only domain controller object that submitted the request.
Let O be the security principal object whose samAccountName attribute matches NBComputerName.
Let Cacheable be the value consistent with locally querying the RODC!msDS-IsUserCachableAtRodc attribute specified in [MS-ADTS] section 3.1.1.4.5.32, where TO=O.
If Cacheable is true, validation succeeds.
Otherwise, validation fails.