How we will see SIA-QUERY and SIA-REPLY?

1)Connect four routers in a row.

2)  (1.1.1.1)R1---R2------R3-----R4(4.4.4.4)

3)Configure EIGRP on all routers.

4)On R3 increase hold time to 1000 seconds.

5)On R3, Create a ACl and block all eigrp unicast packets.

6)On R1

shut the loopback 1, run command show ip eigrp topology and you can see there active timer.

Wait for 3 minutes.(run debug eigrp packets sia-query and reply)