Re: route oddness

[marcs () ZNEP COM (Marc Slemko)]

On Wed, 12 Apr 2000, Mike wrote:

> Been seeing some funny things in my routing table (HP-UX 10.20). Was
> hoping someone could give me some ideas about them. What bothers me is
> that they are all outside the US and seem to be from the same IP
> classes. Are these traces of an exploit or normal traffic? Any ideas would
> be helpful.

Nothing unusual there.  Just how HPUX stores PMTU values discovered
via path MTU discovery.  See http://users.worldgate.ca/~marcs/mtu/
for a description of PMTU-D; it is focused on what can break PMTU-D,
but it also describes what it is and how it works.

HPUX simply stores a route with the MTU info and a certain expiry.