If +/- is used in /etc/passwd, /etc/shadow, and /etc/group files, you will need to modify the nsswitch.conffile to insure compatibility.
NIS+. To provide +/- semantics with NIS+, change the passwd and groups sources to compat and add a passwd_compat: nisplus entry to the nsswitch.conf file after the passwd or group entry as shown below:
passwd: compat passwd_compat: nisplus group: compat group_compat: nisplus
passwd: compat group: compat
This specifies that /etc files and NIS maps as indicated by the +/- entries in the files.
Users working on a client machine being served by an NIS+ server running in NIS compatibility mode cannot run ypcat on the netgroup table. Doing so will give you results as if the table were empty even if it has entries.