Through this topology, I want to decrease the buffer size of R2 in order to generate an ICMP Source Quench Message, but I have no idea how to do it. I'm open to other suggestions to generate a Source Quench Message.
I'm using: Cisco Internetwork Operating System Software IOS (tm) 2600 Software (C2691-ENTSERVICESK9-M), Version 12.3(16)