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I have noticed a couple of messages about my Kerberos credentials expiring.

What does this actually mean and what will happen when they expire?

How do I renew them? Is it just a case of logging in again?


        Message from [ 28 August 2009 01:58:53 BST ] ...

Message to

your kerberos credentials expire in less than 30 minutes.

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up vote 4 down vote accepted

You originally authenticated to the Kerberos Key Distribution Centre (KDC) and were given a ticket-granting ticket (TGT). You used this TGT to get a ticket for your telnet session (from the KDC): the TGT and this ticket are separate things.

The TGT is about to expire. If you want to use it to get any more tickets after this, then you will need to re-authenticate yourself (i.e. obtain a new TGT).

The ticket you currently have for your open telnet session is still valid however, and is unaffected by the TGT expiring.

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Ahh good I was worried that my session containing a long running process would stop working but now you have enlightened me about the TGTs it makes sense. Thanks – pjp Aug 28 '09 at 7:29
"for your open telnet session"? Does anybody still use telnet? – grawity Aug 28 '09 at 8:36
@grawity I still use telnet for some testing :-P – Nerdling Aug 28 '09 at 11:06
Kerberized telnet uses encryption and so isn't really the same issue as old telnet. – chris Aug 28 '09 at 12:37

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