Collecting data from NIS domains
If you’re migrating users and groups from a NIS domain, you can use ypcat or niscat to generate a copy of the NIS passwd and group maps once for each NIS domain. For example, run commands similar to the following:
ypcat passwd > `domainname`.passwd ypcat group > `domainname`.group
If you are collecting user and group information from NIS maps, copy all of the files generated by these commands to a common location for analysis.