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I followed these instructions and got google-authenticator setup on an Ubuntu LiveCD for test purposes. And it doesn't work. I've tried running google-authenticator probably ten times and maybe I'm able to login with a auth token during one or two of those ten attempts I'm unable to login a second time even after I was able to log into it the first time.

Here's the text from my setup screen:

Do you want authentication tokens to be time-based (y/n) n
Your new secret key is: JQJF34XTTHS7HVNF
Your verification code is 935720
Your emergency scratch codes are:

Do you want me to update your "home/ubuntu/.google_authenticator" file (y/n) y

By default, three tokens are valid at any one time. This accounts for
generated-but-not-used tokens and failed login attempts. In order to
decrease the likelihood of synchronization problems, this window can be
increased from its default size of 3 to 17. Do you want to do so (y/n) y

If the computer that you are logging into isn't hardened against brute-force
login attempts, you can enable rate-limiting for the authentication module.
By default, this limits attackers to no more than 3 login attemtps every 30s.
Do you want to enable rate-limiting (y/n) n

Anyway I can't figure it out and pretty much, right now, the only thing google-authenticator is good at, in so far as I'm concerned, is locking everyone, admins included, out of a system, permanently.

Is there something I need to be doing that I'm not?

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Do you really think its wise to post your secret key? –  Ramhound Apr 19 '13 at 12:02
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