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Date: Thu, 17 Jul 2003 19:53:16 +0200
From: Yann Nottara <yann.nottara@almonde.com>
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Subject: Re: MPD 3.13 PPTP server MTU problems & questions
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Andy Gilligan wrote:
> ----- Original Message ----- 
> From: "Yann Nottara" <yann.nottara@almonde.com>

>>Zs you can see in the following real world example, ng0 (which IS up) 
>>MTU stays at 1500 although it's configured to be at 1460 in the mpd.conf
>>configuration file :
>>
>>ng0: flags=8890<POINTOPOINT,NOARP,SIMPLEX,MULTICAST> mtu 1500
>>         inet6 fe80::2b0:d0ff:fee1:4874%ng0 prefixlen 64 scopeid 0x7
> 
> 
> This doesn't look UP to me :)

[...]

> Whenever MPD receives a connection, and assigns that interface to a
> client, it will change the MTU and mark it as UP.
> 
> At least, it does for me...
> 
> Interface down, mpd running, no client connected:
> 
> ng0: flags=8890<POINTOPOINT,NOARP,SIMPLEX,MULTICAST> mtu 1500
>         inet6 fe80::209:5bff:fe2f:692c%ng0 prefixlen 64 scopeid 0x7 
> 
> Client connects:
> 
> ng0: flags=88d1<UP,POINTOPOINT,RUNNING,NOARP,SIMPLEX,MULTICAST> mtu 1396
>         inet 192.168.0.1 --> 192.168.0.2 netmask 0xffffffff 
>         inet6 fe80::209:5bff:fe2f:692c%ng0 prefixlen 64 scopeid 0x7 
> 
> Regards,
> -Andy

Ok, my mistake on this one   :)

but now, what do you think of this ?

ng0: flags=88d1<UP,POINTOPOINT,RUNNING,NOARP,SIMPLEX,MULTICAST> mtu 1500
         inet6 fe80::2b0:d0ff:fee1:4874%ng0 prefixlen 64 scopeid 0x7
         inet 192.168.0.10 --> 192.168.0.200 netmask 0xffffffff

and here's the part from my mpd.conf that's related to this connection :

pptp0:
         new -i ng0 pptp0 pptp0
         set iface disable on-demand
         set iface enable proxy-arp
         set iface idle 3600
         set bundle enable multilink
         set link yes acfcomp protocomp
         set link no pap chap
         set link enable chap
         set link keep-alive 10 60
         set link mtu 1460   <----------------- !
         set ipcp yes vjcomp
         set ipcp ranges 192.168.0.10/32 192.168.0.200/32
         set ipcp dns 192.168.0.10
         set ipcp nbns 192.168.0.10

So, where's the catch ?

--Yann