But what if someone just enters in an ip address on their laptop to be the same as the machine they unplugged...then limiting dhcp to known mac addresses doesn't work. I use this to control who my dhcp server gives ip addresses out to, but that doesn't stop anyone from setting the ip address on their own laptops... -----Original Message----- From: redhat-list-bounces@xxxxxxxxxx [mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of Chiu, PCM (Peter) Sent: Thursday, June 30, 2005 3:11 AM To: General Red Hat Linux discussion list Cc: Chiu, PCM (Peter) Subject: RE: NIS/NFS question I suppose a similar approach with iptables, is to enforce DHCP to known MAC addresses. Peter -----Original Message----- From: redhat-list-bounces@xxxxxxxxxx [mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of Wayne Pinette Sent: 29 June 2005 22:37 To: redhat-list@xxxxxxxxxx Subject: NIS/NFS question I have a question regarding NIS and was wondering if anyone had any ideas. We are creating a Linux workstation lab for students. We have a central linux box which teh students can ssh into from home. The lab is a place where they can log in and work on their work. We are using NIS to authenticate the workstations and we are nfs mounting the /home directory. This is all pretty standard and make sense. Here is the problem : If a student walks into the lab with their laptop running their favourite linux to which they have root access, unplugs a workstation, plugs in their laptop, hardcodes the worksation's ip, sets ups his laptop to nis authenticate and nfs share just like the workstation, logs in as root, he can now su to any student id on the system. Although I quash root on the nfs share, it does not stop this student from getting access to any other students (or instructors) material on the server. Although my nis server only trusts a small list of ip addresses, it's trust is still only based on ip. Is there a way to add some sort of certificate trust to nis or some other mechanism to check against before nis will trust a machine on it network other than just ip? Wayner -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
