pmtud + ipnat RELENG_6_2 appears to be broken

[Stephen Clark]

Stephen Clark wrote:

>Hi List,
>
>When using ipnat, part of ipfilter 4.1.13, I don't see any
>icmp packets being returned saying:
>Host Unreachable, frag needed and DF set.
>type 3, code 4
>
>It does work if I am not using ipnat.
>
>Any ideas?
>
>Thanks,
>Steve
>
>  
>
Sorry for the noise - this seems to be OK. But the problem I am seeing 
relates to:

Did something change in 6.2? If my mtu size on rl0 is 1280 it won't
accept a larger incoming packet.

kernel: rl0: discard oversize frame (ether type 800 flags 3 len 1514 > max
 1294)

I don't think it worked this way in the past.

Won't this affect pmtud?

man page for ifconfig says mtu limits size of "transmission" not reception.

     "mtu n   Set the maximum transmission unit of the interface to n, 
default
             is interface specific."

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