Hadoop has a GroupMappingServiceProvider interface that is used to get group mappings. The commonly used real implementation of that interface is a Shell based mapper that executes shell commands to obtain this information. There has been some work on LDAP and Active Directory based mappers in the community. The Shell based mapper can be made to work on Windows in the following ways
1) Map every user to the same group, say “HadoopUsers”. Currently, this is what has been hard coded and it could be changed to be a configurable group name.
2) Use Windows commands like “net user” to provide the group membership of a given user. This provides both local group memberships and global group memberships. I propose we use this method since it’s a natural extension of the existing feature. It also leverages built-in support on Windows for gathering such information.