[nsp] ICMP: time exceeded (reassembly)

[Bulger, Tim]

> Does it make any difference? As already stated, the tunnel carrier
> packets are being fragmented, not the tunnel payload.

With GRE, the setting of the DF bit from the payload packet is carried
over to the tunnel packet, and as another poster pointed out, there are
subtle differences in the handling of fragmentation between IPIP and
GRE.  Based on all that you've said, it sounds as if there is some buggy
behavior taking place somewhere as no fragmentation should be required
in your environment.

Good Luck 
Tim