IPSec Multipathrouting

IPSec Verbindungen with Multipathrouting

Last adaptation to the version: 12.6.0

New:

Updated to Redesign of the webinterface

notempty

This article refers to a Resellerpreview

11.6

Introduction

Many companies now rely on multipath routing, i.e. several Internet lines on one UTM, for the benefit of performance and also as a failsafe measure. In the following, you will learn what you need to bear in mind for such a setup in conjunction with one or more IPSec tunnels.

Basic configuration of an IPSec Site-to-Site connection

After logging in to the administration interface of the firewall (in the delivery state: https://192.168.175.1:11115), an IPSec connection can be added in the menu VPN IPSec} Button + Add IPSec connection.

Setup Wizard

Step 1 - Connection type
Caption	Value	Description	Add IPSec Connection UTMuser@firewall.name.fqdnVPNIPSec Setup step 1
Selection of the connection type:	The following connections are available. Roadwarrior Site to Site	For the configuration of a Site to Site connection, this one is selected.

Step 2 - General
Name:	IPSec S2S Branch	Name for the connection	Setup step 2
IKE Version:	IKE v1IKE v2 Default: IKEv2	Selection of the IKE version. When using IKE v2 it is possible to combine multiple subnets under one SA (default for newly created connections). Without this option, a separate SA is negotiated for each subnet combination. This has significant disadvantages, especially with numerous SAs, and leads to limitations and losses in the stability of the connections due to the design of the IPSec protocol. This option is activated while editing the phase 2 configuration with the entry Group subnet combinations.

Step 3 - Local
Local Gateway ID:	Any interface	Any string. The gateway ID flows into the authentication. This can be an IP address, a host name or an interface. On the remote gateway, this value must be configured exactly the same way. If an email address should be used as Gateway ID, it is necessary to insert a double @@ in front of the ID (mail@... becomes @@mail@...). Otherwise the ID will be treated as FQDN Automatically filled in for certificate authentication method after certificate selection.	Setup step 3
Authentication method:	Pre-Shared Key	A pre-shared key is in use
Authentication method:	Certificate	A certificate is in use
Pre-Shared Key For authentication method pre-shared key.		An arbitrary PSK
		Creates a very strong key
		Copies the PSK to the clipboard
X.509 Certificate: For authentication method certificate.	Server certificate	Selection of a certificate This certificate must be created beforehand under Authentication Certificates .
Share networks:	» ✕192.168.222.0/24	The local network of the remote gateway to be accessed

Step 4 - Remote Gateway
Remote Gateway:	192.0.2.192	Public IP address (or hostname that can be resolved via DNS) of the remote gateway.	Setup step 4
Remote Gateway ID:	192.0.2.192	ID configured as local ID on the remote gateway (any character string).
Share networks:	» ✕192.168.192.0/24	The local network of the remote gateway to be accessed
Exit the setup wizard with Finish
For S2S connections, it should be checked whether several subnets can be combined via MULTI_TRAFFIC_SELECTOR. This significantly reduces the number of SAs and increases the stability of the connection. To do this, the option Group subnet combinations is activated in phase 2.

Use case 1: Additional PPPoE line

Use case 1

The first possible way to connect an additional line is to connect another ADSL connection in addition to the existing Internet connection (wan0). To configure the second PPPoE line, please refer to this manual.

Configuration with ADSL

In the case of ADSL as the second line, the network configuration under Network Network configuration Area Network interfaces should look as follows:			Network configuration UTMuser@firewall.name.fqdnNetwork Network configuration for ADSL
In this case, phase 1, under VPN IPSec Area Connections Button Phase 1, of the IPSec connection should look like this:
Caption	Value	Description	Edit phase 1 UTMuser@firewall.name.fqdnVPNIPSec Phase 1 configuration for ADSL
IKE Version:	ikev2	Selection of the IKE version. When using IKE v2 it is possible to combine multiple subnets under one SA (default for newly created connections).
Local Gateway:	wan0
Local Gateway ID:	wan0	Any string. The gateway ID flows into the authentication. This can be an IP address, a host name or an interface. On the remote gateway, this value must be configured exactly the same way. If an email address should be used as Gateway ID, it is necessary to insert a double @@ in front of the ID (mail@... becomes @@mail@...). Otherwise the ID will be treated as FQDN Automatically filled in for certificate authentication method after certificate selection.
Remote Host / Gateway:	ipsec.ttt-point.de
Remote Host / Gateway ID:	ipsec.ttt-point.de
Local authentication method:	Pre-Shared Key
Start up behavior:	Outgoing

Use case 2: Additional SDSL line

Use case 2

The second possible way to connect an additional line is to connect an SDSL line in addition to the existing wan0 line. In this case, you have a public IP on the interface and a predefined gateway for this line.

Configuration with SDSL

In the case of SDSL as the second line, the network configuration under Network Network configuration Area Network interfaces is as follows:			Network configuration UTMuser@firewall.name.fqdnNetwork Network configuration for SDSL
In this case, phase 1, under VPN IPSec Area Connections Button Phase 1, of the IPSec connection should look like this:
Caption	Value	Description	Edit phase 1 UTMuser@firewall.name.fqdnVPNIPSec Phase 1 configuration for SDSL
IKE Version:	ikev2	Selection of the IKE version. When using IKE v2 it is possible to combine multiple subnets under one SA (default for newly created connections).
Local Gateway:	LAN3
Local Gateway ID:	203.0.113.0	Any string. The gateway ID flows into the authentication. This can be an IP address, a host name or an interface. On the remote gateway, this value must be configured exactly the same way. If an email address should be used as Gateway ID, it is necessary to insert a double @@ in front of the ID (mail@... becomes @@mail@...). Otherwise the ID will be treated as FQDN Automatically filled in for certificate authentication method after certificate selection.
Remote Host / Gateway:	ipsec.ttt-point.de
Remote Host / Gateway ID:	ipsec.ttt-point.de
Local authentication method:	Pre-Shared Key
Start up behavior:	Outgoing

Rulebook

To grant access to the internal network, the connection must be allowed.

It is possible, but not recommended to do this with implied rules under Firewall Implied Rules section VPN to configure this. However, these Implied Rules release the ports used for IPSec connections on all interfaces.			Implied rules UTMuser@firewall.name.fqdnFirewall Implied rules
notempty As a general rule: Only what is needed and only for the one who needs it is released!
Create network object A network object must be created for the remote network. Firewall Network Objects Button Add Object If several subnets exist on the remote gateway, a network object must be created for each subnet. If the corresponding authorizations are to be assigned, these can be combined into network groups.
Name:	IPSec-S2S	Name for the IPSec S2S network object	Add network Object UTMuser@firewall.name.fqdnFirewallNetwork Objects
Type:	VPN network	Type to be selected
Address:	192.168.192.0/24	The IP address of the local network of the opposite side, as entered in the Installation Wizard in Step 4 - Remote Gateway in the line Share networks. So in this example the network 192.168.192.0/24.
Zone:	vpn-ipsec	Zone to be selected
Group:		Optional: One or more groups to which the network object belongs.

Packet filter rule


First rule
Source:	internal-network	Host or network (-pool), which should get access to the internal network	Packetfilter UTMuser@firewall.name.fqdnFirewall Regeln aktualisieren Packet filter rules
Destination:	IPSec network	Host, network or network group to which access is to be granted. Here, for example, a group of rdp servers.
Service:	benötigter Dienst	Service or service group that is needed
NAT:	Hidenat Exclude
Network Objects:	external-interface

Second rule
Source:	IPSec network	Host or network (-pool), which should get access to the internal network
Destination:	internal-network	Destination
Service:	benötigter Dienst	Service or service group that is needed
NAT:		No NAT

Configuration of the second gateway

notempty

It should be noted that the IKE version is identical on both sides.

Use of a Securepoint UTM

On the remote gateway, the settings must be made in a similar way

A new IPSec VPN connection is created using the IPSec wizard
A network object for the IPSec network is created
Packet filter rules are created

Remote Gateway step 2

The same authentication method must be selected
The same authentication key (PSK, certificate, RSA key) must be available
The same IKE version must be used

Remote Gateway step 3

As Local Gateway ID the Remote Gateway ID from step 4 of the first UTM must now be used
Under Share Networks the (there remote) network from step 4 of the first UTM must also be used

Remote Gateway step 4

The public IP address (or a hostname that can be resolved via DNS) of the first UTM must be entered as Remote Gateway.
(This address was not required in the wizard of the first UTM).
The Local Gateway ID from step 3 of the first UTM must be used as Remote Gateway ID
Under Share networks the (there local) network from step 3 of the first UTM must also be used.

Create network object of the remote gateway

The network object of the remote gateway represents the network of the first UTM.
Correspondingly, the network address of the local network of the first UTM must be entered under Address.
In the example 192.168.218.0/24

Notes

Add Transparent rule UTMuser@firewall.name.fqdnApplicationsHTTP-Proxy Transparent rule

The transparent HTTP proxy

If a server behind the Site-to-Site connection is to be accessed from the internal network via HTTP, the transparent HTTP proxy may filter the packets.
This can lead to errors while accessing the target.
To prevent this from happening, a rule Exclude must be created in the Applications HTTP Proxy Area Transparent mode Button Add transparent rule menu with source internal-network to target name-vpn-network-object and protocol HTTP.

Troubleshooting

Detailed Troubleshooting instructions can be found in the Troubleshooting Guide