UNIX for Dummies Questions & Answers

Hello everyone,

Can anyone help me out where is the maximum unsuccessful login attempts stored in unix?

How can we know how many unsuccessful login attempts an user has made?

Where is the blocked users info maintained or how can we get whether the user is blocked?

Thanks in advance.

That might depend on the version of "Unix" you are using.

Quite sure it is more than "might depend"...
For HP-UX it can depend, depending of OS version of if the server is "trusted" or not also...

Until we know what Operating System you have, this is guesswork. There are proprietary security mechanisms and various connection mechanisms to connect to a unix server. There is no generic answer for all "unix".

For a basic "telnet" connection (where allowed by local rules) a general answer is to read "man login" (It's specific to the machine).
The "telnet" login process is designed to be immune to brute force attack and will not accept typeahead or multiple failed passwords before getting slower and slower to respond and then dropping the connection. You will know that the unix "last" command gives a history of successful logins, but when properly configured the unix "lastb" command gives a history of unsuccessful logins (including the source IP address).

Personally I have never heard the term "blocked users" in the context of unix or Windows Systems Administration (though I can guess what it means).
I do routinely "lock" unix accounts (see "man passwd") and "disable" Microsoft Windows accounts.


Hmm. Sounds like interview questions ... or maybe awkward questions from an auditor?