Hi Rahul
Thanks for your reply.
The current configuration between the 2 interfaces is MC-LAG, there's an ICL-PL Link between them which is a trunk contains all vlan members should be transit under the mclag. i have more some irb units which acts as layer3 for the vlans in the mc-lags. in addition there's a layer2 interfaces that has no vlans.
i don't understand what is the l2 interface for this irb. i don't have ae1.21 (ae1 is the ICL-PL link) and it can't be configured and the mac address is one for all IRB's on the machine.
so, though the article you referred me probobaly would solve this issue, i'm having trouble in understanding on how to implement this.