On Tue, Jun 27, 2006 at 09:52:02AM +0200, forums wrote:
> > Hello,
> >
> > I use BSD3.8 to connect some sites with a VPN tunnel (using the wonderful
> > 'ipsecctl' ).
> >
> > The connections are (more or less) stable, but I have some issues making
> > RDP (Remote Desktop from Micro$oft) connections. It tells me it cannot
> > connect to
> > the remote server (but the ping towards those servers works fine, so its
> > reachable).
> > Sometimes it works fine for hours and then, suddenly, the connection (RDP
> > protocol only, its not the tunnel for sure) is broken.
> >
> > According to a MS note (314825 : http://support.microsoft.com/kb/314825
> > <http://support.microsoft.com/kb/314825> ) this could be a "Black Hole
> > Router Issue" and I should try to set the MTU (Maximum Transmission Unit)
> > lower (the ping with a packet/framesize from 1472 indeed fails over this
> > line). A packetsize from around 1300 works ok.
> >
> > Is there a way to set the MTU size (on the outgoing nic or perhaps the
> > enc0 virtual nic) within BSD?
> > The solution MS offers is to set the MTU on al PC's, but that would be a
> > lot of work and if its possible on the BSD box, it's active for all in one
> > go.
Yes, use ifconfig(8), pf(4) (see pf.conf(5), scrub), or probably any of
the umpteen different solutions.
BTW, to check if this is really an MTU issue, use longer ping packets -
see ping(8), -s.
Joachim
