Is it possible to know a user logged in on Ubuntu instantly?

Posted by Mustafa Orkun Acar on Super User See other posts from Super User or by Mustafa Orkun Acar
Published on 2014-08-23T22:21:43Z Indexed on 2014/08/23 22:24 UTC
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Filed under:

linux

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ubuntu

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iptables

In fact, I am trying to restrict access to some websites for different users. I asked the question: Restrict access to some websites for different users.

The given answer is ok; but as the owner of answer says, it works if users are locally logged in. That is; if the user logs out and logs in, restrictions are no more valid.

So, I decided to run a script including the iptables commands for restrictions at every log in event. I want to know whether it is possible to know instantly the user logs in.

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