Scamper is a program that is able to conduct Internet measurement
tasks to large numbers of IPv4 and IPv6 addresses, in parallel, to
fill a specified packets-per-second rate. Currently, it supports the
well-known ping and traceroute techniques, as well as MDA traceroute,
alias resolution, some parts of tbit, sting, and neighbour discovery.

Scamper can do ICMP-based Path MTU discovery. scamper starts with the
outgoing interface's MTU and discovers the location of Path MTU
bottlenecks. scamper performs a PMTUD search when an ICMP
fragmentation required message is not returned to establish the PMTU
to the next point in the network, followed by a TTL limited search to
infer where the failure appears to occur.