Edit your PAM configuration settings to support the required modules: auth, account, password, and session. If required modules are not defined, the connection will be refused.On Linux systems, the following file is installed with the server:
/etc/pam.d/ssh
This file contains the default configuration information. For example, on SLES systems the ssh file includes the following:
#%PAM-1.0
auth include common-auth
auth required pam_nologin.so
account include common-account
password include common-password
session include common-session
On other systems, create (or configure) /etc/pam.conf. For example, on HP-UX:
ssh auth required /usr/lib/security/libpam_unix.1
ssh account required /usr/lib/security/libpam_unix.1
ssh password required /usr/lib/security/libpam_unix.1
ssh session required /usr/lib/security/libpam_unix.1