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Scientific Linux > Security and privacy > Openssh preauth

Posted by: vicchi Jan 24 2017, 05:37 AM
I got one requirement from our clients regarding remote authentication. In which all users info present in remote user database.

Currently using openssh for SSH connections.
To open a new remote session via SSH, the openssh will look into the /etc/passwd file. If user present then it will allow to login using password or key authentication.

But in my case all user info is present in remote database and authentication is form remote using tacacs+ server.

Due to this I am facing error message as below
2017 Jan 13 10:45:51 : switch : sshd : Invalid user test from
2017 Jan 13 10:45:51 : switch : input_userauth_request: invalid user test [preauth]

Please give some inputs on how to handle this scenario.


Posted by: helikaon Feb 2 2017, 11:19 AM

which SL are you trying to log onto? 6 or 7?
What kind of external database you talk about? LDAP?
Also if you log on the server as a 'root' can you then "su -" to normal user? Will you get the normal user prompt?
What is your "nsswitch.conf" file saying about credential preferences?

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