LinuxQuestions.org
Share your knowledge at the LQ Wiki.
Home Forums Tutorials Articles Register
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Networking
User Name
Password
Linux - Networking This forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.

Notices


Reply
  Search this Thread
Old 05-06-2012, 12:02 AM   #1
SubZeroJake
LQ Newbie
 
Registered: May 2012
Location: San Diego
Posts: 10

Rep: Reputation: Disabled
Question PPTP VPN on Debian VPS (port 1723 Not Open)


I have been trying to setup a vpn for my ipad all weekend long. I believe i have set it up right after all the tutorials I have read. The problem is, when I try and connect, I am told the server is not responding. I also tried on my Ubuntu box, same problem. I did an nmap on my server on port 1723. This told me the port was closed. I put
Code:
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 1723 -j ACCEPT
in my /etc/iptables.conf and no luck. Now I am asking for help. I am running Debian, have reboot, and made sure pptpd is running. Thanks for the help. My VPS provider (Sshvm.com) is running SolusVM.

Last edited by SubZeroJake; 05-06-2012 at 08:37 PM.
 
Old 05-06-2012, 07:27 PM   #2
es0teric
Member
 
Registered: Apr 2007
Distribution: Ubuntu
Posts: 105

Rep: Reputation: 19
Try running 'sudo ss -lnp' on the server. Do you see any process listening on that port?
 
Old 05-06-2012, 08:39 PM   #3
SubZeroJake
LQ Newbie
 
Registered: May 2012
Location: San Diego
Posts: 10

Original Poster
Rep: Reputation: Disabled
Quote:
Originally Posted by es0teric View Post
Try running 'sudo ss -lnp' on the server. Do you see any process listening on that port?
Running
Code:
ss -lnp |grep 1723 yields
Code:
0      0                              *:1723                          *:*      users:(("pptpd",5951,6)
 
Old 05-06-2012, 09:29 PM   #4
scheidel21
Senior Member
 
Registered: Feb 2003
Location: CT
Distribution: Debian 6+, CentOS 5+
Posts: 1,323

Rep: Reputation: 100Reputation: 100
as a test what happens if you clear the firewall rules or shut down the firewall entirely can you connect then? Also make sure the VPS providor isn't blocking any ports into their data center.
 
Old 05-06-2012, 09:39 PM   #5
SubZeroJake
LQ Newbie
 
Registered: May 2012
Location: San Diego
Posts: 10

Original Poster
Rep: Reputation: Disabled
Quote:
Originally Posted by scheidel21 View Post
as a test what happens if you clear the firewall rules or shut down the firewall entirely can you connect then? Also make sure the VPS providor isn't blocking any ports into their data center.
I contacted my VPS provider and they told me that there is no firewall in front of my VPS and that they do not block any ports. Also, not sure what firewall you are talking about, either the non-existent one or iptables. If iptables is a firewall I do not know how to disable it.
 
Old 05-07-2012, 12:07 AM   #6
scheidel21
Senior Member
 
Registered: Feb 2003
Location: CT
Distribution: Debian 6+, CentOS 5+
Posts: 1,323

Rep: Reputation: 100Reputation: 100
Yes IPtables. just clearing all the rules should disable it or disable the IPtables service. You can see what rules all ready exist, maybe you have a higher priority rule over riding the accept rule you set up.

iptables --list

will show you all the rules

iptables --flush

should clear all the rules out.
 
Old 05-07-2012, 12:09 AM   #7
scheidel21
Senior Member
 
Registered: Feb 2003
Location: CT
Distribution: Debian 6+, CentOS 5+
Posts: 1,323

Rep: Reputation: 100Reputation: 100
You should also be able to turn the iptables service off in Debian

/etc/init.d/iptables stop
 
Old 05-07-2012, 12:20 AM   #8
SubZeroJake
LQ Newbie
 
Registered: May 2012
Location: San Diego
Posts: 10

Original Poster
Rep: Reputation: Disabled
Quote:
Originally Posted by scheidel21 View Post
You should also be able to turn the iptables service off in Debian

/etc/init.d/iptables stop
Flushed iptables. No luck.
Code:
/etc/init.d/iptables restart
no such file or directory.
 
Old 05-07-2012, 12:52 PM   #9
scheidel21
Senior Member
 
Registered: Feb 2003
Location: CT
Distribution: Debian 6+, CentOS 5+
Posts: 1,323

Rep: Reputation: 100Reputation: 100
This is very odd. The port isn't getting blocked by your 3G provider or ISP if on WiFi is it? Also have you ensured the GRE protocol can get through too?

From a PC can you try running nmap against your VPS and seeing what it reports for open ports and services that it detects are running?
 
Old 05-09-2012, 11:31 PM   #10
SubZeroJake
LQ Newbie
 
Registered: May 2012
Location: San Diego
Posts: 10

Original Poster
Rep: Reputation: Disabled
Quote:
Originally Posted by scheidel21 View Post
This is very odd. The port isn't getting blocked by your 3G provider or ISP if on WiFi is it? Also have you ensured the GRE protocol can get through too?

From a PC can you try running nmap against your VPS and seeing what it reports for open ports and services that it detects are running?
1. Not sure how to check GRE
2. nmap says port 1723 is closed with service pptpd
3. port 1723 is not blocked by ISP
 
Old 05-10-2012, 04:08 PM   #11
scheidel21
Senior Member
 
Registered: Feb 2003
Location: CT
Distribution: Debian 6+, CentOS 5+
Posts: 1,323

Rep: Reputation: 100Reputation: 100
Maybe uninstall IPTables, at least for testing....?
 
Old 05-10-2012, 10:24 PM   #12
SubZeroJake
LQ Newbie
 
Registered: May 2012
Location: San Diego
Posts: 10

Original Poster
Rep: Reputation: Disabled
Quote:
Originally Posted by scheidel21 View Post
Maybe uninstall IPTables, at least for testing....?
First: WOW this is getting ridiculous and thank you soo much for your help.

I removed iptables - didn't work
Reinstalled iptables - still didn't work
 
Old 05-10-2012, 10:41 PM   #13
scheidel21
Senior Member
 
Registered: Feb 2003
Location: CT
Distribution: Debian 6+, CentOS 5+
Posts: 1,323

Rep: Reputation: 100Reputation: 100
Sorry trying to think about what could be done to troubleshoot it. Obviously from the scan the port is seen as closed. But at this juncture I have to say I don't think it is a firewall running on your VPS, but I'm at a loss as to what it could be.
 
Old 05-13-2012, 11:00 PM   #14
SubZeroJake
LQ Newbie
 
Registered: May 2012
Location: San Diego
Posts: 10

Original Poster
Rep: Reputation: Disabled
Closed

I have made progress. Now, port 1723 is open, only problem is I cannot connect (Thread here: http://www.linuxquestions.org/questi...46#post4677646)
To do this, I enabled PPP under my VPS management client, reinstalled to CENTOS 5, and followed this guide: http://blog.doylenet.net/?p=17.
 
  


Reply

Tags
debian, pptp, vpn



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
PPTP VPN on Debian VPS (port 1723 Closed) SubZeroJake Linux - General 2 05-07-2012 06:20 AM
Need aid understanding -> Centos 6 VPS, VPN, PPTP, DD-WRT Aro2220 Linux - Networking 1 04-04-2012 06:16 PM
how to config a PPTP VPN server in my ubuntu VPS? myjohn2006 Linux - Server 1 03-24-2010 06:13 AM
Closing port 1723 "pptp service" in linux Darwish Linux - Security 7 11-12-2005 04:17 AM
pptp poptop VPN +port omid1979 Linux - Networking 0 06-11-2005 08:29 AM

LinuxQuestions.org > Forums > Linux Forums > Linux - Networking

All times are GMT -5. The time now is 07:33 PM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration