[AusNOG] TPG EFM - low MTU

[Andrew Jones]

I don't think you need to add another 8 on top of the 40 for PPPoE, 
because that part of the frame gets stripped before it goes into the 
l2tp tunnel, unless I'm mistaken...

On 23.06.2014 15:26, McDonald Richards wrote:
> You need to be able to hit a LAC at 1540 bytes from your LNS if you
> don't want to be fragmenting clients. Add another 8 bytes for PPPOE…
>
> Macca
>
>  From: Bruce Forster <bruce at tubes.net.au>
>  Date: Monday, 23 June 2014 3:20 PM
>  To: "ausnog at ausnog.net" <ausnog at ausnog.net>
>  Subject: [AusNOG] TPG EFM - low MTU
>
> Hi Noggers,
>
>  I have a strange issue seems to be isolated to VIC LAC's
>
>  Some session are coming up at MTU 1476.
>
>  I did managed to clear a l2tp tun and the session came back via
> another LAC at 1500.
>
>  These are the ones i have had problems with: TPGVICLAC-6e 
> / TPGVICLAC-5e
>
>  To get around it iv set mtu on the dialer to match and used a 
> mss-adjust...
>
> I can ping to the LAC's IP at 1500 with no issue.
>
>  --
>  Regards,
>
>  Bruce
> _______________________________________________
> AusNOG mailing list
> AusNOG at lists.ausnog.net
> http://lists.ausnog.net/mailman/listinfo/ausnog