Re: [pptp-devel] Re: problem in using pptp-linux.

[James C. <jam...@hp...>]

On Mon, Sep 08, 2003 at 07:38:35AM +0800, James Ng wrote:
> Hi,
>     The school have provided the method for Windows XP
> to connect, and I do it and connect to the Internet
> successfully.
> 
>    In the instruction of Windows XP, my school ask us
> to edit the vpn connection:
> 
> "a) in the Security tab of the properties dialog box
> for the VPN connection, choose Advanced (cution
> settings) and click Settings.
> 
> b)For Data encryption, choose Optional encrytpion. And
> choose Allow these protocols for Logon security. Check
> Unencrypted password(PAP), Microsoft CHAP(MS-CHAP) and
> Microsoft CHAP Version 2 (MS-CHAP v2). Then click OK
> button to finsh the setting."
> 
>    How to do in pptp-linux so that the above
> instruction can work in debian?

I don't know for sure, because I don't use Microsoft Windows, but maybe
someone who does can answer you.  I can say that PPP (which is used by
PPTP) supports PAP, MS-CHAP, and MS-CHAP-V2.  It can also use MPPE, if
the version is in the 2.4.2 range.  I use PPTP on Debian GNU/Linux.  

>    I have encountered some error messages"
> debian:/etc/ppp# pon provider updetach
> debian:/etc/ppp# pon tunnel
> The remote system (PPTP) is required to authenticate itself
> but I couldn't find any suitable secret (password) for it to use to do so.

This is covered in the Diagnosis HOWTO.
http://pptpclient.sourceforge.net/howto-diagnosis.phtml#required_to_auth

Or, if you also saw "(None of the available passwords would let it use
an IP address.)" then you should fix the chap-secrets file to add an
asterisk as the address, which is the fourth field.
http://pptpclient.sourceforge.net/howto-diagnosis.phtml#required_to_auth_ip

> from connect-errors
> anon warn[pptp_gre_bind:pptp_gre.c:95]: connect:
> Network is unreachable

The host name or IP address of the PPTP server is incorrect.
http://pptpclient.sourceforge.net/howto-diagnosis.phtml#connect_unreachable

This error is inconsistent with the "required to authenticate".  You
cannot get "Network is unreachable" followed by "required to
authenticate", unless you have run PPP (e.g. using pon) again after
changing whatever was causing the "Network is unreachable".

> Insteads, my school only provide the instruction for
> the Redhat 7.x to connect. 

The situation has likely changed since your school wrote those
instructions.  You should find out what makes it work with the new
versions and write the new instructions for your school.

> so how to convert them into debian pptp-linux version?

They may not be appropriate for this version of PPTP and PPP.

> ----chap-secrets
> (my login name of my school's vpn) vpn.xxx.xxx.xxx (my password)

Add a space and an asterisk (*) to this line.

> -----peers/tunnel
> pty "pptp vpn.cuhk.edu.hk --nolaunchpppd"

Verify that "vpn.cuhk.edu.hk" can be resolved.  Use the Fault Tree to
test this.
http://pptpclient.sourceforge.net/howto-diagnosis.phtml#fault_tree

-- 
James Cameron                         http://quozl.netrek.org/
HP Open Source, Volunteer             http://opensource.hp.com/
PPTP Client Project, Release Engineer http://pptpclient.sourceforge.net/