I?m setting up some QoS configs for voice and testing them in a Lab
As my test link is 128Kbps, I?m reducing the MTU to say 120.
This is to reduce the effect of serialisation delay, but as soon as I do, everything goes wrong. Pings stop, everything stops, ospf stops
Question, Does changing the MTU force HDLC to fragment large packets into smaller parts or does it simply discard oversize packets ?
Simple one really, but I cannot find on Cisco what exactly MTU does.
Do the MTU settings need to be the same on both ends of the link ?