Re: IPv6 mtu autoconfiguration
On Tue, Oct 31, 2006 at 04:37:06PM +0100, Emiel Kollof wrote: > Op maandag 30 oktober 2006 12:56, schreef Francois Tigeot: > > Hi all, > > > > I am experimenting with IPv6 on a small LAN. All machines use > > Dragonfly-1.6.x. > > The gateway uses a PPPoE ADSL modem, and so is unable to route > > packets > 1492 bytes. > > You can sidestep the whole problem if you can get the modem to do bridging > mode. This is also a way more reliable solution. I think that almost all *DSL > providers support this. Have yet to come across one that doesn't. > > With bridging mode you can throw that shakey pppoe solution in the circular > filing cabinet and use a plain dhcp client to get an IP, default gateway and > whatever. Well, I'm afraid I can't do that and still have *IPv6* connectivity. My only sensible option is to use Dragonfly's user ppp client. Anyway, I have found a workaround with pf. I am just curious about the whole rtadvd client mtu stuff. -- Francois Tigeot
Re: IPv6 mtu autoconfiguration
Op maandag 30 oktober 2006 12:56, schreef Francois Tigeot: > Hi all, > > I am experimenting with IPv6 on a small LAN. All machines use > Dragonfly-1.6.x. > The gateway uses a PPPoE ADSL modem, and so is unable to route > packets > 1492 bytes. You can sidestep the whole problem if you can get the modem to do bridging mode. This is also a way more reliable solution. I think that almost all *DSL providers support this. Have yet to come across one that doesn't. With bridging mode you can throw that shakey pppoe solution in the circular filing cabinet and use a plain dhcp client to get an IP, default gateway and whatever. Cheers, Emiel -- There are many times when you want it to ignore the rest of the string just like atof() does. Oddly enough, Perl calls atof(). How convenient. :-) -- Larry Wall in <[EMAIL PROTECTED]> pgpY26HvWZqVx.pgp Description: PGP signature
IPv6 mtu autoconfiguration
Hi all, I am experimenting with IPv6 on a small LAN. All machines use Dragonfly-1.6.x. The gateway uses a PPPoE ADSL modem, and so is unable to route packets > 1492 bytes. With IPv4, TCP MSS is reduced automagically by ppp. Since there is no such trick for v6 tcp connections, I have tried to force a smaller IPv6 MTU on the client machines by setting up rtadvd with these options on the gateway: vr0:\ :mtu#1280: rtadvd runs fine, and I can the advertisements for a 1280 bytes MTU broadcast on the LAN. Client machines pick up their adresses and network mask correctly, but their MTU stays at the 1500 bytes ethernet default. Any TCP connection to a v6 connected host on the Internet thus fails. AFAIK, the only way I have found to reduce an interface MTU is by using ifconfig manually. Is this the intended behavior ? What's more, by using ifconfig manually, the interface MTU is changed for both IPv4 and IPv6 protocols. There is no way to specify a v4 or v6 only behavior. This may be related to the previous issue. I hope someone can shed some light on this. -- Francois Tigeot
