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Questions tagged [l2tp]

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.

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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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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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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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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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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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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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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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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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Configuring L2TP VPN to use with iOS 14 and macOS Big Sur

After Apple did this in Big Sur OS I can't connect to my own VPN on Libreswan 3.27 (netkey) on 3.10.0-1160.6.1.el7.x86_64 Starting with iOS 14 and macOS Big Sur (coming soon), IPsec supports HMAC-SHA-256 with L2TP VPN. To make sure that VPN client…
megamosk
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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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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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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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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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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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