Common operational misconceptions

Valdis.Kletnieks at Valdis.Kletnieks at
Mon Feb 20 14:42:15 UTC 2012

On Mon, 20 Feb 2012 15:42:56 +0900, Masataka Ohta said:
> George Bonser wrote:
> >> It is seemingly working well means there is not much PMTU changes,
> >> which means we had better assumes some PMTU (1280B, for example) and
> >> use it without PMTUD.
> > It depends on the OS and the method being used.  If you set the
> > option to "2" on Linux, it will do MTU probing constantly and
> > react to MTU changes.
> It actually does nothing.

Did you find this by just reading RFCs, or by actual code inspection?

> the hosts are keep assuming PMTU of 1400B and if local MTU
> is 1500B or less, no discovery is performed because "the
> probe size range is small enough".

And if the local MTU is 9000?
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