Topic: Ubuntu and VPN on SME

[Fumetto]

I have a bit of a problem, I can not run the VPN with SME. Let me explain.
On my computer I use two operating systems, Windows XP and Ubuntu Linux 9.10.
On Windows XP when I have configured the VPN it works correctly, on Linux I have not found a way to make it run.
I use Gnome and the NetworkManager applet but even on manual configure not work.

I followed the steps on site of pptpclient...

/etc/ppp/chap-secrets

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# Secrets for authentication using CHAP
# client server secret IP addresses

"tonino" TestSME "xyz123" *
/etc/ppp/peers/TestSME

Code: [Select]

pty "pptp PUBLIC_IP_OF_SME --nolaunchpppd"
name "tonino"
remotename TestSME
require-mppe-128
file /etc/ppp/options.pptp
ipparam TestSME
but when I launch a VPN connection...

Code: [Select]

fumetto@fumetto-desktop1:~$ sudo pon TestSME debug dump logfd 2 nodetach
pppd options in effect:
debug # (from command line)
nodetach # (from command line)
logfd 2 # (from command line)
dump # (from command line)
noauth # (from /etc/ppp/options.pptp)
refuse-pap # (from /etc/ppp/options.pptp)
refuse-chap # (from /etc/ppp/options.pptp)
refuse-mschap # (from /etc/ppp/options.pptp)
refuse-eap # (from /etc/ppp/options.pptp)
name tonino # (from /etc/ppp/peers/TestSME)
remotename TestSME # (from /etc/ppp/peers/TestSME)
# (from /etc/ppp/options.pptp)
pty pptp PUBLIC_IP_OF_SME --nolaunchpppd # (from /etc/ppp/peers/TestSME)
crtscts # (from /etc/ppp/options)
# (from /etc/ppp/options)
asyncmap 0 # (from /etc/ppp/options)
lcp-echo-failure 4 # (from /etc/ppp/options)
lcp-echo-interval 30 # (from /etc/ppp/options)
hide-password # (from /etc/ppp/options)
ipparam TestSME # (from /etc/ppp/peers/TestSME)
proxyarp # (from /etc/ppp/options)
nobsdcomp # (from /etc/ppp/options.pptp)
nodeflate # (from /etc/ppp/options.pptp)
require-mppe-128 # (from /etc/ppp/options.pptp)
noipx # (from /etc/ppp/options)
using channel 21
Using interface ppp0
Connect: ppp0 <--> /dev/pts/1
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
LCP: timeout sending Config-Requests
Connection terminated.
Modem hangup
Waiting for 1 child processes...
  script pptp PUBLIC_IP_OF_SME --nolaunchpppd, pid 30785
Script pptp PUBLIC_IP_OF_SME --nolaunchpppd finished (pid 30785), status = 0x0
fumetto@fumetto-desktop1:~$
Maybe not the right place because I seem to be a bigger problem than Ubuntu but after a couple of days I do not know what corner of the wall banging my head... someone could help me or indicate the way for my head?

Sorry for not perfect language...

[CharlieBrady]

Connect: ppp0 <--> /dev/pts/1
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x9395dde5> <pcomp> <accomp>]
LCP: timeout sending Config-Requests
Connection terminated.

http://pptpclient.sourceforge.net/howto-diagnosis.phtml#lcp_timeout

[Fumetto]

Thanks, but I was hoping someone could tell me if there is something in the configuration that is wrong ... if someone uses the VPN with Ubuntu, perhaps I could help.

However I will try to follow the guide. the first time I tried did not come at the head of anything ...

[Stefano]

Thanks, but I was hoping someone could tell me if there is something in the configuration that is wrong ... if someone uses the VPN with Ubuntu, perhaps I could help.

in this case I suggest you to ask in ubuntu's forums as it seems to be a ubuntu's issue and not a SME one

ciao

[CharlieBrady]

However I will try to follow the guide.

There is no alterative to following the guide. As it says, there are many possible causes of LCP timeout. The most likely one is a firewall somewhere between the two ends which is blocking/dropping GRE packets.

[Stefano]

There is no alterative to following the guide. As it says, there are many possible causes of LCP timeout. The most likely one is a firewall somewhere between the two ends which is blocking/dropping GRE packets.

well.. but OP said that his pc is in dual boot and everything is working in windows.. so, IMO, it's a misconfiguration on Ubuntu side, not a  environmental one..

my 2€c

[Fumetto]

... The most likely one is a firewall somewhere between the two ends which is blocking/dropping GRE packets.

I do not understand why but Ubuntu stop incoming GRE packet... I think...
I observe tcpdump in action and when Ubuntu send gre packet did not receive anything
Thanks for the support, try to ask in the Ubuntu forums... but nobody uses linux to connect with the VPN on SME ... possible?!?!

[chris burnat]

Moving this topic to General Discussions where it is more appropriate.

[Fumetto]

No reply on the Ubuntu forum... I try again in SME forum 

I try the guide for troubleshotting and create my.tcpdump file. I open the file whit wireshark and the result is this

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10 1.180920 192.168.1.10 IP_SERVER TCP 55643 > pptp [ACK] Seq=325 Ack=189 Win=6912 Len=0 TSV=2352172 TSER=467949034
11 1.181141 192.168.1.10 IP_SERVER PPP LCP Configuration Request
...
repeat row 11 for 9 time and then
...
21 31.038286 192.168.1.10 IP_SERVER PPTP Call-Clear-RequestWhy the packet sended from computer to SME not receive reply?!?! 

[CharlieBrady]

Why the packet sended from computer to SME not receive reply?!?! 

Two possible reasons:

SME is not sending any reply packets.

Something between SME server and Ubuntu is not passing the reply packets.

[warren]

Have you tried installing the NetworkManager Applet :
http://www.gnome.org/projects/NetworkManager/

This worked for me on Ubuntu 9.10 ( test machine )

[Fumetto]

SME is not sending any reply packets.

I do not think... on Windows client SME is full functional

Something between SME server and Ubuntu is not passing the reply packets.

Sure ... but why? and what? 

Have you tried installing the NetworkManager Applet :
http://www.gnome.org/projects/NetworkManager/

This worked for me on Ubuntu 9.10 ( test machine )

Is included in standard ubuntu installation seems... you have installed it from site?

[Fumetto]

YESSSSSSSSSSSSSSSSSSSSSSS!!!

Now VPN go up!!!
The "bug" is Linux Security Module AppArmor...
In a terminal I insert a command

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sudo /etc/init.d/apparmor stopand magically VPN go up and full functional.

Now I understand how and why AppArmor does not allow the operation of the VPN and how not to stop the service to run the VPN... but thi is another story...