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I have an OpenVPN setup and my clients authenticate with my server using the keys I've generated through pkitool.

The problem is that the clients can share the keys with others and effectively allow many others to connect through my VPN. How can I impose a restriction that a client key can only be used for one connection at a time?


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up vote 5 down vote accepted

you should check for the directive "duplicate-cn" in server.conf configuration file. Make sure it's NOT uncommented.

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Thanks but I tried that and I can still login with the same key from two clients simultaneously. – recluze Feb 10 '11 at 8:56
Oh, got it. The wording was a little convoluted but it works. Thanks. – recluze Feb 23 '11 at 3:28

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