Permanently change MAC address on Libra 2

[ajkessel]

This worked: I added a file /etc/udev/rules.d/98-set-mac.rules:

KERNEL=="wlan*", ACTION=="add", RUN+="/usr/local/Kobo/udev/fix_net"

and then fix_net is:

#/bin/sh
MAC='mac address here'
ip link set dev wlan0 down 
ip link set dev wlan0 address $MAC
ip link set dev wlan0 up

So the final workflow is to authenticate with an Apple device using its built-in hardware MAC address; then switch the Apple device to randomize MAC (to avoid duplication); then when the Kobo boots up it can access the network using the previously-authenticated MAC address.

[jgneff]

For what it's worth, a long time ago I had luck adding an exit hook to the DHCP response, as follows:

# /etc/dhcpcd.exit-hook - sets the host name from DHCP data
# In Ubuntu: /lib/dhcpcd/dhcpcd-hooks/30-hostname (dhcpcd5)
# Called by: /libexec/dhcpcd-run-hooks
if $if_up; then
    if [ -n "$new_host_name" ]; then
        hostname "$new_host_name"
    fi
fi

I wanted to set the host name as provided by my router in the DHCP response, but perhaps you could set the MAC address here instead.

[ajkessel]

Originally Posted by jgneff

For what it's worth, a long time ago I had luck adding an exit hook to the DHCP response, as follows:

# /etc/dhcpcd.exit-hook - sets the host name from DHCP data
# In Ubuntu: /lib/dhcpcd/dhcpcd-hooks/30-hostname (dhcpcd5)
# Called by: /libexec/dhcpcd-run-hooks
if $if_up; then
    if [ -n "$new_host_name" ]; then
        hostname "$new_host_name"
    fi
fi

I wanted to set the host name as provided by my router in the DHCP response, but perhaps you could set the MAC address here instead.

Thanks. Does anyone know if the network/dhcp process flow for Kobo is documented somewhere? One concern I have with setting the MAC address there is that in order to force the MAC address, you need to bring the interface down first or you get an error.. and this hook seems to be one that is called when the interface is coming up? So is there a chance of an infinite loop?

[jgneff]

Originally Posted by ajkessel

One concern I have with setting the MAC address there is that in order to force the MAC address, you need to bring the interface down first or you get an error..

Right, the exit hook might be too late. I'm not sure when the enter hook is called, but perhaps that's an option. See dhcpcd-run-hooks.8 for more information.

[DNSB]

Not to mention that if you change the MAC address after the DHCP address is received, the router will not consider it a valid address when the IP address to MAC address translation is done.