I’ve been testing sssd with realmd to connect to Active Directory (on Windows 2012 R2).  I’ve managed to get most of the functionality working OK, including GPO filters to manage user access.

 

However, when the user fails to log in due to GPO rules, it doesn’t give any meaningful message, it just drops the SSH connection – e.g.

[~]$ ssh bob@jr-centos

bob@jr-centos's password:

Connection closed by 192.168.56.11

[~]$

 

The target host logs this in /var/log/secure:

Jan 12 11:20:41 jr-centos sshd[2892]: pam_sss(sshd:auth): authentication success; logname= uid=0 euid=0 tty=ssh ruser= rhost=[REDACTED] user=bob

Jan 12 11:20:41 jr-centos sshd[2892]: pam_sss(sshd:account): Access denied for user bob: 6 (Permission denied)

Jan 12 11:20:41 jr-centos sshd[2892]: Failed password for bob from 192.168.56.98 port 45070 ssh2

Jan 12 11:20:41 jr-centos sshd[2892]: fatal: Access denied for user bob by PAM account configuration [preauth]

 

Operating system is Centos 7.3.1611.  SSSD software versions:

[root@jr-centos tmp]# rpm -qa | grep sssd

sssd-common-pac-1.14.0-43.el7_3.4.x86_64

sssd-krb5-common-1.14.0-43.el7_3.4.x86_64

sssd-krb5-1.14.0-43.el7_3.4.x86_64

sssd-ad-1.14.0-43.el7_3.4.x86_64

sssd-client-1.14.0-43.el7_3.4.x86_64

sssd-common-1.14.0-43.el7_3.4.x86_64

 

To be clear, the configuration is working fine, I don’t expect bob to get access to the jr-centos server and I can get user “bob” to log in if I add him to the relevant AD group.  However, the abrupt SSH disconnection is not very user friendly and something like “Access denied due to policy” or whatever would be more useful.  Is the lack of useful (any) message due to something in my environment, or does this require a feature request/improvement?

 

John Riddoch