[Openswan Users] ipsec/l2tp with nat traversal

Paul Wouters paul at xelerance.com
Wed Apr 26 20:52:32 CEST 2006

On Wed, 26 Apr 2006, Trevor Benson wrote:

> > Did you set a lower then 1500 mtu on your external interface on the
> l2tp
> > server? Did you set mtu/mru to 1200 in the l2tpd.conf? Which l2tpd are
> > you running?

> mtu 1200
> mru 1200

That answered part of my question.

> Well this is a connection from a site that has another site to site
> tunnel running on it to the same gateway, and has for years.  No traffic
> issues from the site to site, would the mtu settings in options not
> account for whatever would be required if leaving a standard 1500 has
> worked for years (and is working while all this testing is going on).

The two networks are different right? The old connection might not have
the same mtu resitrctions as the new client you're adding. MTU issues
depend on each hop travelled, and can change pretty suddenly.

Building and integrating Virtual Private Networks with Openswan:

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