Can't ping throught bond interface?

I've the following situation:



interface bond0 in mode active-backup with eth1 and eth2. Before I create the bond interface, I can ping, that is directly connected throught eth1. But when I create the bond interface, also if the interface eth1 is active, I can't ping no more Why is this happening? Is there a problem with the bond address and the two interfaces addresses? My OS is OpenWrt