On Wed, May 5, 2010 at 4:09 AM, Marco Giunta <[email protected]> wrote: > Hi at all, > I'm a sysadmin in an Italian college; for security reason, our PXE > server allows only few and well known MAC addresses. When I change mac > address with gPXE command: > > gPXE> set net0/mac ff:ff:ff:11:22:33 > > and then I check new mac address with: > > gPXE> show net0/mac > net0/mac = ff:ff:ff:11:22:33 > > it seems changed, but if I want to get a DHCP address, with: > > gPXE>dhcp net0 > > I receive 'Connection timed out' error. > With Wireshark, I found that mac address is not changed, but is only > spoofed; in fact, every ethernet frame send by the card has as source > address the original network card mac address, but DHCP request has done > with new mac address (ff:ff:ff:11:22:33). Of course, our dhcp server, > replies with a DHCP offer to new mac address, so the network card cannot > accept the offer. > > My question is: is this behaviour right ? I mean, command 'set netX/mac' > should be only use for spoofing mac address in network request, or > should really change mac address, like unix command 'ifconfig eth0 hw > ether ff:ff:ff:11:22:33' ??
For almost all drivers, the MAC address needs to be set before the card is initialized. Thus, you should do gPXE> ifclose net0 gPXE> set net0/mac ff:ff:ff:11:22:33 gPXE> ifopen net0 gPXE> dhcp net0 -- Josh > > Thank you, > Marco > > _______________________________________________ > gPXE mailing list > [email protected] > http://etherboot.org/mailman/listinfo/gpxe > _______________________________________________ gPXE mailing list [email protected] http://etherboot.org/mailman/listinfo/gpxe
