Ran into the same issue as kvspb/nginx-auth-ldap#7 but with auth_pam instead of auth_ldap (using pam for ldap auth though)
- auth_pam will prompt if on it's own
- auth_pam will not prompt if satisfy any and IP limits
Used the solution to issue 7 and added a blank basic auth file. IP and PAM work.
satisfy any;
allow 192.168.100.0/24;