If you are working with Linux clients you can try with hostObject and pam_ldap

http://wiki.debian.org/LDAP/PAM
http://moduli.net/sysadmin/sarge-ldap-auth-howto.html
https://help.ubuntu.com/community/LDAPClientAuthentication

By default you need an * value for host if you want your users can login on any machine.
To modify the host value when a user is logged you can put some lines to modify its value with the IP of that machine modifying:

/etc/gdm/PreSession/Default

When the user close her session to return the host's value to * you can modify:

/etc/gdm/PostSession/Default

Regards.

2010/11/23 Olivier PAVILLA <olivier.pavilla@univ-orleans.fr>
I would like to know if it's possible to prevent many loggings on many
computers from only one user?
I have LDAP/Samba server. Anyone must connect with LDAP to acces its
home. So I have user who opened 12 computers, logged on those 12
computers and
ran boinc-client on those 12 computers... I want to prevent this kind of
behaviour...

--
Luis Antonio Galindo Castro aka FunkyM0nk3y
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