Packet forwarding during boot

[david at betterspot.com]

Hi,
I have a MT7620A board with 2 ethernet ports. I connect the WAN port to 
another router and the LAN port to my laptop. During boot, my laptop 
gets an IP address from the parent router, because it seems that kernel 
is forwarding packets when lede has not started up completely.
When boot finished I should renew my laptop's dhcp lease to get an IP 
from lede.
Why is this happening?
How can I fix it?

Regards
David