Results 1 to 2 of 2

Thread: Prevent User from being able to change IP

  1. #1
    Join Date
    Apr 2007

    Prevent User from being able to change IP

    Hi all,

    We have dhcpd server running on RHEL AS 4. If on a client, user sets a static IP and then sets it to be a dynamic, his machine gets the same IP from the DHCP server rather than what it was given before by the DHCP server.


    Step 1 :

    Machine set to Dynamic, IP Obtained:

    Step 2 :

    Machine assigned a static IP :

    Step 3:

    Machine set back to Dynamic, Obtained IP :

    In this scenario, in the third step a machine should have got the old one IP i.e. but it didnt get that one. Why is it so? This allows user to have whatever IP he wants. (It is very serious issue when Internet access is given on the IP addresses )

    What setting can I do on this, as users having administrative rights can easily change their dynamic IP.

    (I am not looking for the solution through Group Policy in Windows Domain Environment.)

    Please suggest.......

  2. #2
    Join Date
    Jan 2007
    Adelaide, Australia

    Thumbs up RE: Prevent User from being able to change IP

    Why don't you configure DHCPd to assign ip addresses based on the MAC address of the machine that is requesting the lease? Eg: As taken directly from Peter's page

       # You can also assign specific IP addresses based on the clients'
       # ethernet MAC address as follows (Host's name is "laser-printer":
      host laser-printer {
          hardware ethernet 08:00:2b:4c:59:23;
    This will only assign the address and no other address to the printer. Change this to reflect your own MAC address and host name in your servers dhcp.conf (usually in /etc/ ). Also make sure users cannot change their MAC address on the machine they are using!


Similar Threads

  1. Prevent my users from spamming and making ddos attacks
    By gueurk in forum Linux - Hardware, Networking & Security
    Replies: 0
    Last Post: 01-22-2012, 12:55 PM
  2. Way to prevent SIGKILL
    By J::2 in forum BSD
    Replies: 2
    Last Post: 05-12-2009, 07:29 PM
  3. Replies: 2
    Last Post: 08-06-2007, 12:34 PM
  4. can't change user data or passwords!!!!
    By gschlut in forum Linux - General Topics
    Replies: 2
    Last Post: 02-26-2004, 08:27 PM
  5. Prevent root login with ssh
    By friskydrifter in forum Redhat / Fedora
    Replies: 2
    Last Post: 12-06-2002, 10:02 AM


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts