How to Identify NIS Authenticated Users

This post describes how to identify Network Information Service (NIS) authenticated users.

1. To obtain a complete list of all NIS users, run the ypcat passwd command For example:

[root@nisserver ~]# ypcat passwd
test2:x:504:504::/home/test2:/bin/bash
user1:x:501:501::/home/user1:/bin/bash
user2:x:502:502::/home/user2:/bin/bash
user3:x:503:503::/home/user3:/bin/bash

2. To identify whether a specific user is a NIS user, run the ypmatch [username] passwd command.

– If the given user exists within the NIS database, expect output such as the following:

[root@nisserver ~]# ypmatch user1 passwd
user1:x:501:501::/home/user1:/bin/bash

– If the user does not exist within the NIS database, expect output such as the following:

[root@nisserv ~]# ypmatch test passwd
Can't match key test in map passwd.byname. Reason: No such key in map