PPTP with MPPE connection freezes after a few seconds

oneself

Hi All,

I've been trying to connect to my office's VPN with not success for
the past few weeks. A few seconds after connecting successfully the
connection freezes up will issueing repeated "Protocol-Reject for
unsupported protocol 0x9a89". Please let me know what information I
should post to help resolve this problem, and thank you kindly for
your help.

I'm using gentoo kernel 2.6.16-r7.

I use ppp with the following setup:

Katphish · Apprentice Joined: 05 Dec 2005 Posts: 155

Hi,

What kind of server are you connecting to?

I suspect your MRU/MTU are probably wrong. I would get the same log messages with GRE and then pppd would get out of sync.

Windows based pptp devices seem to favor an MTU of 1400. There is a bug somewhere and I forget where exacly it is but I use:

oneself · Posted: Thu Jun 01, 2006 3:22 pm Post subject:

Hi and thanks for the help,

I tried setting the mtu/mru as you suggest,
but it does not seem to have any effect.

Is there any more information I can supply
that would help diagnose the problem?

Thanks

oneself · Posted: Thu Jun 01, 2006 8:39 pm Post subject:

I've noticed that the first error in the logs is:

superwutze · Posted: Mon Jul 31, 2006 3:15 pm Post subject:

i'm fighting with the same problems now for pretty long.

the error you get (flushed bit) results of incompatible software. the old kernel modules for mppe/mppc are gone as of 2.6.15. since then there is a kernel implemented module for mppe, but mppc is gone. with a kernel as of 2.6.15 and above you have to disable the mppe-mppc use-flag.
_________________
bill who? micro what?

oneself · Posted: Wed Aug 02, 2006 3:19 am Post subject:

Thank you very much for your response.
I've removed mppe-mppc flag from my USE variable in make.conf,
and I'm trying to re-emerge ppp. However, when I do, I still
get it:

These are the packages that would be merged, in order:

Calculating dependencies... done!
[ebuild R ] net-dialup/ppp-2.4.3-r16 USE="gtk ipv6 mppe-mppc pam -activefilter -atm -dhcp -eap-tls -radius" 727 kB

I've tried adding "-mppe-mppc" but that doesn't seem to help either.

How do I get rid of this flag?

Thanks

oneself · Posted: Wed Aug 02, 2006 3:55 am Post subject:

I managed to re-emerge by running:

superwutze · Posted: Thu Aug 03, 2006 7:20 am Post subject:

this howto helped me a lot, it also describes the differences in the config file.
_________________
bill who? micro what?

oneself · Posted: Fri Aug 04, 2006 12:02 am Post subject:

Thanks for your help, however, this howto is geared for
pre-2.6.15 kernels that need to be patched for mppe-mppc
support. I need a reference from someone who managed
to connect to an MS VPN with a new kernel.

Has anyone actually managed to do this?

oneself · Posted: Fri Aug 04, 2006 12:12 am Post subject:

Sorry, upon actually reading the howto it seems
to have all the info I need. I'll go throught
and rebuild everything.

oneself · Posted: Sun Aug 06, 2006 2:59 am Post subject:

Hi,

The Wiki you posted was EXTREMELY helpful.

I got rid of my previous configuration completely,
and starte from scratch. By following the instructions
in the HOW-TO, I managed to set up my vpn correctly,
and now it works.

One small thing that is still not clear, however, is how
to configure my system to have ppp0 start when calling
"/etc/init.d/net.ppp0 start". The how-to seems to suggest
that once I mamange to start the vpn correctly with "pon"
I should be able to just use "/etc/init.d/net.ppp0 start".
However, that script does not exists. I tried linking net.eth0
to net.ppp0. But all I get is:

superwutze · Posted: Mon Aug 07, 2006 10:10 am Post subject:

as i do not start my vpn-connections by default i don't know that, but take a good look into /etc/conf.d/net.example. there is a whole bunch of documentation inside.
_________________
bill who? micro what?