I just though it might be easier for me to share my working configs than keep asking for more details. <interface ID> is a decimal or hex ( 0x prefix) 32-bit number. Now you should have an IPsec GRE tunnel running between two hosts. In this article, the strongSwan tool will be installed on Ubuntu 16.04 (LTS), I will show the integration of OpenSC for hardware tokens and finally the creation of a gateway-to-gateway tunnel using a pre-shared key and x.509 certificates. Paso 5: Configurar la autenticación de VPN. OSPF does maintain reachability. Из спортивного интереса состыковал по IPSec Juniper SRX и OpenWRT (StrongSWAN) с использованием X509-сертификатов для взаимной аутентификации. How to Set Up IPsec-based VPN with Strongswan on Debian and Ubuntu IPsec Tunnel Between IOS Router and Cisco VPN Client 4.x for Windows with TACACS+ User Authentication Configuration Example 14/May/2009. Introducción. Configure StrongSwan on Ubuntu 18.04 /etc/ipsec.conf configuration file specifies most configuration and control information for the strongSwan IPsec subsystem.It consists of three different section types: CONFIG SECTIONS (config setup) - It defines general configuration parameters CONN SECTIONS (conn <name>) My IP: 10.244.251.210 Theirs: 10.244.251.209 Subnet: 10.244.251.208/30. (Later on do dynamic routing with BGP, but make sure GRE works first.) Конфиг ждунипера выглядит примерно следующим образом. Image_gre_ipsec.png . Site to Site GRE tunnel over IPsec (IKEv2) using DNS . The HUB is a Linux Machine (Ubuntu 18.04) running Strongswan 5.9.4. Site-to-site IPSec through NAT - MiViLiSNet Beside this single issue, the network is stable and work well. GRE over IPSec in Cisco IOS | Rayanfam Blog I think this might help you if you accidentally missed something. To ensure prefragmentation in most cases, we recommend the following MTU settings: • The crypto interface VLAN MTU associated with the IPsec VPN SPA should be set to be equal or less than the egress interface MTU. If the tunnel is in the below state then the tunnel has formed correctly: "Tunnel100 is up, line protocol is up". vi /etc/ipsec.conf. . The GRE packets generated by the router are usually sent without the DF bit and can . Itâ s been a while so not sure if there is a simpler way, but then ran BGP over the GRE tunnel for dynamic routing EKG. /sbin/sysctl -a | grep ipsec If you need NAT Traversal, add the following option to your kernel config: options IPSEC_NAT_T Install FreeBSD Port / Package The easiest way to install strongSwan on FreeBSD is to use the security/strongswan port cd /usr/ports/security/strongswan/ && make install clean or to install the binary package with