Quote:
ypcat shadow | grep <username> returns nothing
What is happening here is that the shadow file is (a) not being exported by the Linux server or (b) not being recognized by the AIX client. I'm currently not running NIS here, and I don't recall exactly where to look for it, but there is a file which describes which IPs and subnets which tables can be sent to. You need the shadow file so that passwords can be tested. There is, however, a compatibility mode where Linux will send the encrypted password in the request for the user's entry in the passwd table. Then, however, you won't see an "x". When you run the commands on AIX, where you root? If not, try "ypcat passwd |grep
<username>" again but with your root account.
I'm not sure why su works differently, but there's a way to check: Does AIX use PAM (Pluggable Authentication Modules)? You can test this by looking in /etc/ for a file named pam.conf or a directory named pam.d.