[nsp] weird gre tunnel...

[Oliver Boehmer (oboehmer)]

> On Mon, Apr 19, 2004 at 12:34:42AM -0400, James wrote:
> > And I found out that when you turn OFF cef on the Cisco, the TTL
> > problem with the gre tunnel immediately goes away, and the hidden
> > hop in the traceroute now shows up as expected.. So it appears cef
> > implementation on the IOS versions I tried (12.0.25S1 on 7500,
> > 12.2(17a) on 2610) has a bug or anamolgy that causes it to not
> > decrement the TTL on gre tunnels.. 
> 
> Yes, I've stumbled over the same problem here. IOS does not decrement
> TTL when a packet is forwarded into a GRE tunnel if CEF is enabled on
> the ingress interface. Observed on 12.2(17) mainline.
> 
> CSCea77189 ("Packet to be switched into a tunnel does not decrement
> TTL") matches perfectly from the description of the problem,
> but the affected versions do not match. :-)

This DDTS only applies to Cat6k code.

> There is another bug (CSCdv04959) for "TTL is not decreased while
> switching packets coming from GRE tunnel".

This one fixes the problem (also when switching to the tunnel) for other
platforms.

	oli