Re: nd6_setmtu0: new link MTU on iwn0 (576) is too small for IPv6 which needs 1280

[christos%zoulas.com@localhost (Christos Zoulas)]

On Dec 3,  7:23pm, ottavio2006-netbsd%yahoo.com@localhost (Ottavio Caruso) wrote:
-- Subject: Re: nd6_setmtu0: new link MTU on iwn0 (576) is too small for IPv6

| Hi Christos,
| 
| before launching wpa_gui the MTU is set to 1500, after connecting to
| the router it is 576. I can ping the router and any site fine, simply
| I cannot reach them using http.
| 
| If I am not wrong I could turn off path MTU discovery on NetBSD with:
| 
|  sysctl -w net.inet.ip.mtudisc=0
| 
| Can you confirm me that?

Yes.

| I also guess that the router wants to speak IPv6 and makes some error.
| How could I turn IP6 altogether?

Unfortunately there is no sysctl node for that.
You could recompile a new kernel, or use a packet filter to drop all
ipv6 traffic.  There was a thread about that:

https://mail-index.netbsd.org/netbsd-users/2012/06/27/msg010930.html

Perhaps we should ask kre@ for his patch, or recreate it.

christos