Re: Travel router part 2

[Joerg Sonnenberger <joerg%bec.de@localhost>]

On Sun, Sep 02, 2018 at 12:37:25PM -0400, D'Arcy Cain wrote:
> On 2018-09-02 12:10 PM, Robert Swindells wrote:
> > 
> > D'Arcy Cain <darcy%NetBSD.org@localhost> wrote:
> >> On 2018-09-02 10:03 AM, Robert Swindells wrote:
> >>>> The idea is to use re0 as my DSL connection and later to use athn1 in
> >>>> the campgrounds as I travel.  Here is the relevant portion of my rc.conf.
> >>>
> >>> Maybe use wm0 as the external interface.
> >>
> >> What would that give me?
> > 
> > You trimmed the paragraph of my reply that described what it would give
> > you.
> 
> Sorry, I thought that it was unrelated.  Are you saying that using wm0
> would allow me to set the MTU but re0 doesn't?
> 
> > If you don't have an MTU of 1500 on pppoe0 you will have to deal with
> > MSS-clamping for your internal networks.
> 
> # ifconfig pppoe0 mtu 1508
> ifconfig: SIOCSIFMTU: Invalid argument

The mini-jumboframes have to be on the parent interface of pppoe0, i.e.
wm0. IIRC also before you creating/assigning pppoe0 to it.

Joerg