[c-nsp] MTU / BGP

[Gert Doering]

hi,

On Tue, Jul 21, 2015 at 09:02:12AM +0000, CiscoNSP List wrote:
> re path mtu failing...ME(New)->RR(New), MTU 9100, RR(New) links, All our own network(So we can run whatever MTU we like) -> rest of network to get to "old" RR's is via a third party L2 service, and has max MTU 1978...this is set on the egress Interfaces...should path discovery have worked here? 

If you can 

  ping $otherdevice size 10000

from any device to any device, your L3 MTUs are set up right and path
MTU / MSS discovery should have worked (note: no "df" here) [and fragments
are not being filtered].

If you can't ping a device with big packets, there is a MTU mismatch
somewhere - machines on two ends of a L2 segment not agreeing on the L3
MTU, or the L3 MTU being too high for the L2 segment.

gert
-- 
USENET is *not* the non-clickable part of WWW!
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Gert Doering - Munich, Germany                             gert at greenie.muc.de
fax: +49-89-35655025                        gert at net.informatik.tu-muenchen.de
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