Frequently Asked Questions
Issues related to specific HPC machines are not covered in this FAQ.
This FAQ covers NRL site specific issues.
To contact user support staff, see User support
General Issues:
- How do I change my shell?
- When I log in, the system cannot find my home directory
- I cannot cd into my home directory
Kerberos error messages differ slightly between client operating systems. If you cannot find a closely related error message listed below, please send a detailed description of the problem and all errors messages to User support
- How to download the Kerberos kit
- Getting credentials:
- SSH:
- Krlogin/Krsh:
- kcmd to host hostname failed - No credentials cache file found.
- kcmd to host hostname failed - Ticket expired.
- Other:
General Issues:
- How do I change my shell?
-
Contact User support
- When I log in, the system cannot find my home directory.
-
Your Kerberos credentials were not forwarded or your OpenAFS home directory is temporarily unavailable.
Check to see if your Kerberos credentials were forwarded by running the klist command. If you do not have a krbtgt service principal listed, you will need to reconfigure your client software to forward your Kerberos credentials. SSH users, see The SSH client is not forwarding my Kerberos credentials.
- I cannot cd into my home directory.
-
Your Kerberos credentials have expired, your Kerberos credentials were not forwarded or your OpenAFS home directory is temporarily unavailable.
Check to see if your Kerberos credentials have expired or were not forwarded by running the klist command.
If your credentials are expired, get new credentials and log back in.
If you do not have a krbtgt service principal listed, you will need to reconfigure your client software to forward your Kerberos credentials. SSH users, see The SSH client is not forwarding my Kerberos credentials.
Kerberos Issues:
- How to download a Kerberos kit
-
HPC provides downloadable Kerberos client kits. It is important that you follow exactly the installation directions in the README file. For more information, see the HPC Users Kerberos web page.
- Getting credentials:
- Cannot contact any KDC for requested realm
-
Your computer successfully sent out a request, but the KDC never responded. The network is probably down between your host and the KDC, or you are behind a local host or network firewall.
- Cannot resolve KDC for requested realm.
-
There may be a problem with your local host's DNS hostname to IP address lookups. Contact your local support staff if DNS lookups continue to fail.
- Cannot find KDC for requested realm.
-
The specified Kerberos realm does not seem to exist. Make sure the realm name is entered in all UPPERCASE. Check the local Kerberos configuration file for a missing realm entry.
- SSH:
- The SSH client is not forwarding my Kerberos credentials.
-
By default, the SSH client is not configured to forward your Kerberos credentials. Edit your SSH client configuration and set the following to yes.
-
GSSAPIAuthentication
GSSAPIDelegateCredentials - Krlogin/Krsh:
- kcmd to host hostname failed - No credentials cache file found.
-
You do not have any Kerberos credentials. Get a Kerberos ticket on your local machine.
- kcmd to host hostname failed - Ticket expired.
-
Your Kerberos ticket has expired. Get a new Kerberos ticket on your local machine.
- kcmd to host hostname failed - No credentials cache file found.
- Other:
- Any error message with "clock skew".
-
Your local computer time is more than 5 minutes off the correct time. Check and correct the time, timezone, and daylight savings settings.
- I am behind a firewall, and I am having problems using Kerberos.
-
For Kerberos to work, your client will need to send and receive traffic the Kerberos KDCs. If you need assistance with this matter, contact User support.
- Any error message with "clock skew".