System Preparation

Installing the Kerberos GSSAPI client and server utility

RedHat, CentOS or Scientific Linux

On RedHat, CentOS or Scientific Linux, install the Kerberos GSSAPI utilities by running the following command (as root):

Debian or Ubuntu

On Debian or Ubuntu, install the Kerberos GSSAPI utilities by running the following command (as root):

Troubleshooting

To troubleshoot a GSSAPI connection, you require two separate terminal sessions and a RadSec connection to your local Moonshot RP Proxy.

RadSec connection

On a Moonshot client

Moonshot clients do not need to define a RadSec connection (because the service you connect to defines this connection), if you however are trying to troubleshoot the local GSS system, you will need to define this connection to temporarily turn your Moonshot client into a server.

To do this, you need three files from your Moonshot RP Proxy's FreeRADIUS directory: ca.pem, client.pem and client.key.

Store the files in a directory that an ordinary user can read, and check that the files are also readable by an ordinary user. You may wish to rename them to be clearly identifiable.

Also create a /etc/radsec.conf file by following the instructions to .

Make sure that the file is also readable by an ordinary user.

On a Moonshot server

As part of , you will have defined the RadSec connection configuration.

Check the permissions of the four files needed for a RadSec connections:

Also check the validity of the certificates used for the connection:

Terminal 1 - As root

1. In the first terminal, as root, run the following command:

   
   

2. You should now have the following output with no prompt:

   
   

Terminal 2 - As your test user

In an X environment

When you launch a terminal from X, e.g. a Gnome or KDE desktop session, the behaviour is different to a pure text environment. This is also the case when you use SSH to connect to a remote server and use display forwarding.

1. In a second terminal, as your test user, run the following command:

   powershell

   
   

2. You should now be prompted to select an identity in . Choose one that will authenticate locally.

In a non-X environment

In a pure command-line environment with no display forwarding available, the Moonshot Identity Selector is not available. Instead, you use the .gss_eap_id file to test your environment.

1. In the second terminal, as your test user, create the .gss_eap_id file in your home directory with the following content:

   
   

2. Then run the following command:

   powershell

   
   

GSS Output

After selecting your identity, you should now see output in both terminals.

Successful output

1. In Terminal 1 (as root), the output should scroll rapidly with a lot of hex text before ending with something similar to the following:

   
   

2. In Terminal 2 (as your test user), the output looks similar to the below (in this example, the hostname is debian7x64.localdomain):

   
   

Failed output

If the GSSAPI connection failed, you may see one or more errors in either window.

1. In Terminal 1, you should see one or more messages similar to the below:

   
   

2. In Terminal 2, you should see one or more error messages similar to the below:

   
   

Possible solutions

If your GSS connection failed, you will need to diagnose why the error occurred.

The .gss_eap_id file

A common mistake involves the naming of the .gss_eap_id file on non-X Moonshot clients.

A simple list command as your test user will allow you to check for it:

If you get a "No such file or directory" error message, double-check that the file exists in the home directory of the user you are running the gss-client command as.

GSS directory permissions

Standard users need to have access to the /etc/gss directory and its contents. Check that the permissions allow your test user to list and read the contents:

Hostname

GSS relies on hostnames being correct. Running the hostname and then the hostname -f commands should return the same result:

If the results are different, you must configure your machine correctly to return the same result.

Either define the name correctly in DNS, or configure the /etc/resolv.conf and /etc/hostname or /etc/sysconfig/network files correctly, or install dnsmasq or a similar utility that will use the /etc/hosts file to correctly resolve your hostname.

Connection

Check that there is no firewall preventing the connection. Often a basic firewall like iptables is installed on the local machine. Check whether you can connect to the Moonshot RP Proxy by trying to connect to port 2083 on the Moonshot RP Proxy over TCP. A "Connection refused" message or a connection timeout is usually a tell-tale sign that something is preventing your connection between your local machine and your Moonshot RP Proxy.