Layer 2 Tunnelling Protocol is a layer 7 networking protocol which provides an unsecure layer 2 tunnel. It runs on top of UDP, and is commonly used to carry PPP sessions. Security is usually provided with the addition of IPsec.
Questions tagged [l2tp]
203 questions
25
votes
3 answers
Which ports for IPSEC/LT2P?
I have a firewall/router (not doing NAT).
I've googled and seen conflicting answers. It seems UDP 500 is the common one. But the others are confusing. 1701, 4500.
And some say I need to also allow gre 50, or 47, or 50 & 51.
Ok, which ports are…
hookenz
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Is it possible for L2TP VPN to do auto route configuration for client during connected?
We've setup a L2TP VPN server with this tutorial, everything works like a charm.
The only issue is
We don't want client to route all traffic using this VPN, only a particular subnet, e.g. 10.0.0.0/20
On Mac, we need to set the route manually using…
Howard
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10
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L2TP/IPSec from Windows 7 to ASA 5520
I am trying to setup L2TP/IPSec on our ASA5520 to support a fringe case for one of our developers. The Windows VPN subsystem apparently stores the kerberos or NTLM cookie for the login when you use the built-in vpn subsystem, and the Cisco VPN…
Peter Grace
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8
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1 answer
If IPSec has its own IP tunnel support why do some add LT2P to the stack?
I understand that you can use IPSec to tunnel data securely. According to the Wikipedia page and a few other sources it can also tunnel IP packets and then route them through an interface. That would create a VPN where one subnet would be able to…
Silverfire
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Simple L2TP/IPsec server not working (openswan, xl2tpd, Ubuntu, Windows)
I configured openswan and xl2tpd on an Ubuntu 12.04 server (on EC2) by following various tutorials/documentation which seem to largely say the same things, but most recently this one.
However, my attempts to connect from Windows (which I configured…
Yang
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6
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3 answers
L2TP client for Ubuntu
It's easy enough to get a pptp client going on a Ubuntu 9.04 (Jaunty) desktop:
sudo apt-get install network-manager-pptp
However, I can't seem to find documentation find a corresponding L2TP client to connect to our Windows VPN server at work…
nedm
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5
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1 answer
How do I bypass my VPN when making requests to IPs in my local network?
I have L2TP VPN connection on my Ubuntu laptop and I want to connect to a server in my local network. How do I do so by bypassing the VPN connection?
Alexander Suraphel
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5
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Setting up site-to-site IPsec in bridged mode
I'd like to set up site-to-site IPsec in bridged mode: that is, where the hosts in each site don't need to be modified to use the IPsec gateway, but the IPsec gateway acts as a pseudowire.
My plan to do this is:
Set up host-to-host IPsec on each…
SRobertJames
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5
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1 answer
VPN server not responding, no indications of blocked traffic
I have a Mac OS X Server (10.9) machine running a L2TP/IPSec VPN server. Configuration appears to be fine, and the hostname of both the server and the VPN is set to a DynDNS hostname. The server is configured behind an AirPort Extreme router with…
jstm88
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4
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1 answer
How to setup L2TP IPsec VPN server on Windows Server 2008 R2?
The Windows 2008 R2 (SBS) machine was earlier setup to run a PPTP VPN server. Due to security concerns I do want to replace the PPTP by L2TP/IPsec VPN server.
The server is behind a NAT router where 3 forward rules to the Windows Server are…
Pro Backup
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4
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1 answer
Forwarding VPN via reverse SSH tunnel
I have a server that reverse ssh tunnels to a secondary server. The secondary server then acts as a "bridge" to the internal server (the external server's IP address is what I connect to).
This works fine for most services (files, ssh, etc.) but…
jstm88
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4
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2 answers
I can connect, but cannot ping/route to remote VPN computers
Setup:
L2TP VPN Server on a Windows Server 2008 machine which is behind a router, which is behind a modem/router.
Modem/Router (IP: 192.168.2.1, Subnet: 255.255.255.0, DHCP serves 192.168.2.2 to router)
----|_ Router (IP: 192.168.2.2, Subnet:…
JakeTheSnake
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4
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3 answers
L2TP server allows connections through firewall for iPhone/iPad, but not windows
Our L2TP server (running Windows 2008 RRAS) is behind a NAT firewall. I've already verified that it is passing NAT-T. The firewall rules are all set up correctly to pass GRE, IKE, L2TP and there are no custom IPSEC policies running on the server.…
Eric Falsken
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4
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No TCP connections to hosts behind VPN server (SYN, SYN-ACK, but no ACK), UDP, ICMP works
I'm probably doing something incredibly stupid, but I just can't seem to figure out what. Here's what I'm trying to accomplish: I want remote users to be able to log into our network, so I set up a Windows 2008 Server as a VPN Server inside as a VM…
zakharov
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What is difference between L2TP and PPTP?
I need a high performance VPN server, who can tell me the difference between L2TP and PPTP ?
larry
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