traceroute Fails with -F (do not fragment bit) Argument

With traceroute-1.4a12-XX  the -F argument is used to avoid intra-switch fragmentation. From traceroute(8) manpage:

       -F     Set the "don’t fragment" bit.

When ‘-F’  is specified the traceroute fails to get connected. Even with localhost:

# traceroute -r -F
traceroute to (, 30 hops max, 46 byte packets
 1  * * *
 2  * * *
 3  * * *

Without ‘-F’ it works just fine:

# traceroute -r
traceroute to (, 30 hops max, 46 byte packets
 1  localhost.localdomain (  0.629 ms  0.032 ms  0.021 ms

There is a bug with the IP_DF (don’t fragment flag) in the traceroute-1.4a12 implementation. 

The traceroute had been rewritten from scratch and been ported to OEL5
starting with 1.0.3 (and as of November 27, 2008 the latest is 
traceroute-2.0.1-3.el5 on OEL5) and that series do not have such a

The old traceroute-1.4a12 series are not maintained anymore in favor of the new traceroute (The one from

With traceroute-1.4a12 series do not use the ‘-F’ argument for traceroute. If it
is crucial to have the functionality, only  for 2.6 kernels it is still possible to download the latest source tarball from (2.0.12 as of November 27, 2008) and build it on the distribution.

traceroute-1.4a12 source from –

latest traceroute source from –

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