I'm on Ubuntu 12.10. I have several (12) USB to Ethernet Adapters which all show the same mac address assigned by the kernal, this is a problem since I'm using them to communicate with real switches to simulate a cisco lab w/ GNS3 and the switches think there are routing loops :O
That aside I've tried to set the mac addresses with both macchanger and ifconfig, and they do change but for about 5 minutes then they revert back to their mac's all being the same (except for 2 of them for some reason those two #7 & 8 seem to be keeping their assigned mac.
Now I have read that changing the macs via /etc/networking/interfaces would do the trick, but when I tried for just a single NIC my Ubuntu installation would not boot, hung and had to be repaired (remove that config) before able to boot again. I don't want this to happen, and I'm thinking perhaps the syntax was older/incorrect
This is what I used previously:
iface net1 inet dhcp
hwaddress ether 01:02:03:04:05:06
2nd issue is that I've had to add entries to /etc/udev/rules.d to make sure the usb NICs are assigned interfaces based on their port, and upon reboot they are assigned the incorrect interface unless I unplug and replug them then they are assigned correctly. I'm sure there must be a way to refresh this with a script so I do not have to unplug/replug so if someone could enlighten me I would be eternally grateful!
If it helps here is what that config looks like:
4 Port PCI Bottom Port 1 (from left)
SUBSYSTEMS=="usb", ACTION=="add", KERNELS=="12-1:1.0", NAME="net1"
#4 Port PCI Bottom Port 2 (from left)
SUBSYSTEMS=="usb", ACTION=="add", KERNELS=="12-2:1.0", NAME="net2"
#4 Port PCI Bottom Port 3 (from left)
SUBSYSTEMS=="usb", ACTION=="add", KERNELS=="13-1:1.0", NAME="net3"
#4 Port PCI Bottom Port 4 (from left)
SUBSYSTEMS=="usb", ACTION=="add", KERNELS=="13-2:1.0", NAME="net4"
Thanks in advance I've been working on this several days and am at my wits end!