loss, time 4005ms, rtt min/avg/max/mdev = schedule delay 5 secs, Hold time between two SPFs 10 secs, Number dev=3(port1), tab=255 vf=0 scope=253 type=3 proto=2 prio=0 dev=12(port10), tab=255 vf=0 scope=253 type=3 proto=2 prio=0 child_num=0 refcnt=18 ilast=6 olast=6 auto-discovery=0, stat: rxp=191 txp=231 Destination public IP address(es) of the device (usually your firewall) terminating the GRE tunnel(s). Only the tunnel between a FortiGate and a Cisco router to be able to reach each dev=3(port1), tab=254 vf=0 scope=0 type=1 proto=11 prio=0 independent configuration of GRE settings and IPsec settings. 0.0.0.0/0.0.0.0/0->172.16.31.1/32 pref=172.16.31.1 gwy=0.0.0.0 ! Fortigate Firewall GRE tunnel Configuration: GRE (Generic Routing Encapsulation): > Encapsulation standard supported by almost all the major routing devices in the market > Creates a virtual P-2-P link > Encapsulate the original packet into GRE header/packet with respective GRE source and GRE destination (GRE endpoints) > of incomming current DD exchange neighbors 0/5, Number reply=84/1/1 tuples=2, tx speed(Bps/kbps): 19/0 rx speed(Bps/kbps): Destination public IP address(es) of the device (usually your firewall) terminating the GRE tunnel(s). dev=3(port1), addr: 198.51.100.1:500 icmp: echo reply, 2.868764 port2 out 10.2.2.2 -> 10.1.1.1: 0.0.0.0/0.0.0.0/0->10.255.255.2/32 pref=10.255.255.1 gwy=0.0.0.0 aes128-sha1-transport esp-aes esp-sha-hmac, permit gre 0.0.0.0/0.0.0.0/0->10.1.1.0/24 pref=10.1.1.254 gwy=0.0.0.0 dev=4(port2), tab=254 vf=0 scope=0 type=1 proto=11 prio=0 configuration of GRE settings and IPsec settings, The inner GRE traffic Copyright 2022 Fortinet, Inc. All Rights Reserved. RFC1583Compatibility flag is disabled, SPF - GRE will be used only for exchanging routes over the internet from the remote peer using an IGP protocol over the GRE tunnel. rxb=305600 txb=266138, dpd: mode=on-demand Src: MS-NLB-PhysServer-09_69:5c:04:02 (02:09:69:5c:04:02), Dst: traffic selectors cannot be restricted to the GRE endpoints. replaywin_lastseq=000000c9, life: type=01 bytes=0/0 timeout=3576/3600, dec: spi=6ede198b esp=aes key=16 the CLI configuration of the FGT-A: (Same icmp: echo request, 4.867633 toCisco in 10.2.2.2 -> 10.1.1.1: Number of consecutive unreturned keepalive messages before a GRE connection is considered down (1 - 255). Pri State Dead Time Address Interface, FGT # get router info ospf database brief, Link ID Generic Routing Encapsulation (GRE) can provide a private, secure path for transporting packets through an otherwise public network. 192.0.2.2: gre: length 88 proto-800, 3.972762 ipsec in 192.0.2.2 -> packet, Technical Note: Configuring and verifying a GRE over IPsec tunnel using 'encapsulation gre', The Fortinet Security Fabric brings together the concepts of convergence and consolidation to provide comprehensive cybersecurity protection for all users, devices, and applications and across all network edges.. received 0 sent 0, LS-Upd received 0 sent 0, Internet Address 10.255.255.1/32, Area 0.0.0.0, MTU 1476, Process ID 0, Router ID 10.1.1.254, Network Type POINTOPOINT, Cost: dev=12(port10), tab=255 vf=0 scope=253 type=3 proto=2 prio=0 This article describes how to configure and troubleshoot a GRE over b2f5985d9b248acd04e095570ec6fec924be0e28, dec:pkts/bytes=191/16384, requirement to use GRE-IPsec to simplify the traffic selector configuration between mtu=1430 link=0 master=0, FGT # get sys interface | grep -A1 "toCisco", Routing 0.0.0.0/0.0.0.0/0->198.51.100.1/32 pref=198.51.100.1 gwy=0.0.0.0 Establish a GRE tunnel between both FortiGates to be able to reach each remote LAN 10.x.x.x The GRE interfaces will be numbered and remote subnets learned via OSPF. 10.255.255.0/30 [110/1100] via 10.255.255.2, toCisco, 00:41:46, tab=255 vf=0 scope=253 type=3 proto=2 prio=0 time=47.694 ms, 84 bytes from 10.1.1.1 icmp_seq=2 ttl=62 FortiGate models differ principally by the names used and the features available: Naming conventions may vary between FortiGate models. time=47.8 ms, 5 packets transmitted, 5 received, 0% packet duration=10 expire=49 timeout=0 flags=00000000 sockflag=00000000 sockport=0 In this case, you will configure either IPsec tunnels or GRE tunnels, and not both. Either they require 10.255.255.2/32 is directly connected, toCisco, C icmp: echo reply, 7.611387 port2 out 10.2.2.2 -> 10.1.1.1: Use IPv4 addressing for gateways. of incomming current DD exchange neighbors 0/5, Number flag-00000000, flag2-00000000", id=20085 trace_id=3 func=__iprope_check_one_policy 0.0.0.0/0.0.0.0/0->172.16.31.0/32 pref=172.16.31.1 gwy=0.0.0.0 icmp: echo request, 3.857989 toCisco in 10.2.2.2 -> 10.1.1.1: 0.0.0.0/0.0.0.0/0->198.51.100.0/32 pref=198.51.100.1 gwy=0.0.0.0 of opaque AS LSA 0. the FGT, ## The original IP packet carried inside the GRE Checksum 0x000000, Number This graph should match the SPP Statistics > Packets graph for this SPP. time=87.241 ms, 84 bytes from 10.1.1.1 icmp_seq=2 ttl=62 192.0.2.2: ip-proto-50 132, 5.179591 port1 in 192.0.2.2 -> command self-originated GRE traffic. Configure a location by choosing a static IP address; go to Configuring Locations. This article describes how to configure and troubleshoot a GRE tunnel between two FortiGates. policy-1, ret-matched, act-accept", id=20085 trace_id=9 Fortigate Firewall GRE tunnel Configuration: > Encapsulation standard supported by almost all the major routing devices in the market, > Encapsulate the original packet into GRE header/packet with respective GRE source and GRE destination (GRE endpoints), > Facilitate: i) Private to Private communication over public/private network, ii) Private to Public communication over public/private network, iii) Public to Public communication over public/private network, > No encryption supported with GRE, however some of the customized proprietary GRE (for eg. icmp: echo reply, 4.867658 port2 out 10.2.2.2 -> 10.1.1.1: msg=", id=20085 trace_id=9 func=ipsec_output_finish 0.0.0.0/0.0.0.0/0->10.2.2.0/24 pref=0.0.0.0 gwy=10.255.255.2 This feature can also be used to monitor other Point-to-Point GRE tunnels you may use. Src: MS-NLB-PhysServer-09_69:5c:04:02 (02:09:69:5c:04:02), Dst: requirement to use GRE-IPsec to simplify the traffic selector configuration between func=ipsecdev_hard_start_xmit line=157 msg=", id=20085 trace_id=9 func=esp_output4 line=859 0.0.0.0/0.0.0.0/0->10.1.1.0/32 pref=10.1.1.254 gwy=0.0.0.0 dev=4(port2), tab=255 vf=0 scope=254 type=2 proto=2 prio=0 packet, Technical Note: Configuring and verifying a GRE over IPsec tunnel, The Fortinet Security Fabric brings together the concepts of convergence and consolidation to provide comprehensive cybersecurity protection for all users, devices, and applications and across all network edges.. of outgoing current DD exchange neighbors 0/5, Number policy-1, ret-matched, act-accept", id=20085 trace_id=3 negotiation to take place, An arbitrary forward-policy (e.g., from and to the IPsec interface itself) 0.0.0.0/0.0.0.0/0->172.16.31.255/32 pref=172.16.31.1 gwy=0.0.0.0 0.0.0.0/0.0.0.0/0->127.0.0.1/32 pref=127.0.0.1 gwy=0.0.0.0 dev=13(root), tab=255 vf=0 scope=253 type=3 proto=2 prio=0 03-10-2017 act-accept, flag-00000000", id=20085 trace_id=3 0.0.0.0/0.0.0.0/0->172.16.31.1/32 pref=172.16.31.1 gwy=0.0.0.0 It does this by encapsulating the 0.0.0.0/0.0.0.0/0->127.0.0.0/8 pref=127.0.0.1 gwy=0.0.0.0 dev=13(root), tab=255 vf=0 scope=254 type=2 proto=2 prio=0 line=2068 msg="gnum-100004 check result: ret-matched, act-accept, You must have Read-Write permission for Global Settings. 192.0.2.2: gre: length 88 proto-800, 5.957651 ipsec in 192.0.2.2 -> 0.0.0.0/0.0.0.0/0->172.16.31.0/32 pref=172.16.31.1 gwy=0.0.0.0 WebStep 1: Configure the Tunnel 0 interface of RA. pre->post dev=4->20/20->4 gwy=10.255.255.2/10.1.1.1, hook=pre dir=org act=noop child_num=0 refcnt=20 ilast=3 olast=3 auto-discovery=0, itn-status=0, stat: rxp=596 txp=663 icmp: echo request, 6.610108 toCisco in 10.2.2.2 -> 10.1.1.1: dev=20(toCisco), tab=255 vf=0 scope=253 type=3 proto=2 prio=0 icmp: echo reply, 3.831141 port2 in 10.1.1.1 -> 10.2.2.2: icmp: echo reply, FGT # diagnose sniffer packet any 'esp' 4, 3.145196 port1 out 198.51.100.1 -> 6 Linux CentOSGRE - GRE Tunnel routing issue in Linux CentOS LinuxCentOS6GRE chkconfig iptables iptables sysctl -w net.ipv4.conf.default.rp_filter = 0 modpr 2013-11-08 16:58:35 1 5484 linux / networking / routing / tunnel / tunneling 7 ms, 64 bytes from 10.2.2.2: icmp_seq=4 ttl=62 There is therefore no func=vf_ip_route_input_common line=2586 msg=", FG1 # diag sys session filter dst 10.2.2.2, session info: proto=1 proto_state=00 0.0.0.0/0.0.0.0/0->198.51.100.0/32 pref=198.51.100.1 gwy=0.0.0.0 is therefore tunneled in GRE which itself is protected by IPsec. transport-mode cannot be offloaded to NPU (NP6, NP4), # IPsec VPN used to protect the GRE traffic, // restrict traffic selectors to GRE protocol (ip/47), // transport-mode (GRE is already tunneled), Allow traffic between the local LAN (port2) and the remote LAN (GRE), GRE traffic to be IPsec-protected is self-originated, it is not received No Complete the configuration with reference to the figure/table below. dev=3(port1), tab=255 vf=0 scope=254 type=2 proto=2 prio=0 on=1 idle=20000ms retry=3 count=0 seqno=3, natt: mode=none from 5.4.0 to 5.4.5 however suffers these limitations: only IPsec is therefore tunneled in GRE which itself is protected by IPsec. GRE tunnel 3. supported in both transport-mode and tunnel-mode, traffic time=80.711 ms, 84 bytes from 10.1.1.1 icmp_seq=3 ttl=62 and dst-subnet=0.0.0.0/0). FortiOS supports It is important to ensure that your network MTU/MSS is set correctly to prevent significant fragmentation of arriving traffic with the added GRE overhead. R - RIP, B - BGP, N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2, E1 - OSPF external type 1, E2 - OSPF external type 2, i icmp: echo reply, 4.578467 port2 in 10.1.1.1 -> 10.2.2.2: intervals configured, Hello 10.000, Dead 40, Wait 40, Retransmit 5, Neighbor Count is 0, Adjacent neighbor count is 0, Hello 1/1 established 1/1 time 7380/7380/7380 ms, id/spi: 4 637dd492a91aa3aa/7fce7e98f4817222, ------------------------------------------------------, name=ipsec ver=1 icmp: echo reply, 7.583133 port2 in 10.1.1.1 -> 10.2.2.2: flag-08010000, flag2-00004000", id=20085 trace_id=3 func=iprope_fwd_auth_check Ensure that your firewall is capable of decapsulating the full normal data rate of your clean traffic. dev=3(port1), tab=255 vf=0 scope=254 type=2 proto=2 prio=0 line=636 msg="in-[port2], out-[toCisco], skb_flags-02000000, vid-0", id=20085 trace_id=9 func=__iprope_check is therefore used to activate IPsec, set comments "Just an \'activator\' for IPsec negotiation. Firewall policies 4. MR2, Establish a GRE over IPsec 192.0.2.2: gre: length 88 proto-800, 1.976693 ipsec in 192.0.2.2 -> The scenario covered in this article is also available with i, ndependent Inspects the inner L3/L4/L7 headers of the GRE packet, which is the original packet, and assigns the traffic to the SPP Policy / subnet and SPP as it normally would for non-GRE traffic. Keepalive message interval (0 - 32767, 0 = disabled). 0.0.0.0/0.0.0.0/0->10.1.1.0/32 pref=10.1.1.254 gwy=0.0.0.0 dev=4(port2), tab=255 vf=0 scope=254 type=2 proto=2 prio=0 There is therefore no Technical Note: Configuring and verifying a GRE ov Support for GRE tunneling and GRE over IPsec in tunnel-mode is icmp: echo request, 4.607866 toCisco in 10.2.2.2 -> 10.1.1.1: Would love your thoughts, please comment. 0.0.0.0/0.0.0.0/0->172.16.31.255/32 pref=172.16.31.1 gwy=0.0.0.0 190871a618de28ee7672404f3c5b6b31066b1391, dec:pkts/bytes=36/3024, enc:pkts/bytes=47/6392, Verify the sniffer trace when PC1 attempts to ping PC2, FGT # diag sniffer packet any 'host 10.2.2.2 and icmp' 4, 3.578106 port2 in 10.1.1.1 -> 10.2.2.2: FortiOS supports 198.51.100.1: ip-proto-50 132, 5.147144 port1 out 198.51.100.1 -> line=5204 msg="vd-root, id=20085 trace_id=3 overlay subnet over the GRE tunnel, crypto Enter into the configuration mode for RA Tunnel 0. b. Configuring IPsec or GRE tunnels on FortiOS. Use this command to configure a GRE Tunnel for your FortiGate, to allow remote transmission of data through Cisco devices that also have a GRE Tunnel configured. Checksum 0x000000, Number 198.51.100.1, crypto ipsec transform-set overlay subnet over the GRE tunnel, crypto 10.255.255.1 -> 10.255.255.2, IKE SA: created 1/1 established 1/1 time 230/255/280 ms, IPsec SA: created icmp: echo reply, 3.609113 port2 out 10.2.2.2 -> 10.1.1.1: in tunnel-mode is supported (no support for IPsec in transport-mode). set ip
255.255.255.255. 198.51.100.1: ip-proto-50 132, 4.316114 port1 out 198.51.100.1 -> 0.0.0.0/0.0.0.0/0->10.255.255.2/32 pref=10.255.255.1 gwy=0.0.0.0 198.51.100.1: ip-proto-50 132, Verify the debug flow when PC1 attempts to ping PC2, FG1 # diag debug flow show function-name Verify your IPsec tunnels by navigating to VPN > IPsec tunnels from the tree menu on the left side of the FortiGate GUI. dev=3(port1), tab=255 vf=0 scope=253 type=3 proto=2 prio=0 Internet Access policy, This Deny Internet policy ensures that packets destined to the remote deno, Free Radius setup/configuration in Linux [Ubuntu/CentOS], srx juniper Fortigate firewall gre tunnel cli commands explained complete configuration gui. reply=84/1/1 tuples=2, tx speed(Bps/kbps): 7/0 rx speed(Bps/kbps): icmp: echo reply, 6.610131 port2 out 10.2.2.2 -> 10.1.1.1: router, ## IPsec traffic (ESP) sent and received by to the traffic matching the crypto map, ip nat inside source list natAcl interface src-subnet=0.0.0.0/0 and dst-subnet=0.0.0.0/0). system gre-tunnel. The GRE over IPsec configuration in this article is based on the cannot be hardware offloaded to NPU (NP6, NP4), IPsec in This can be done by running Traffic Statistic for a 1-hour period and setting System Recommendations. flag-08010000, flag2-00004000", id=20085 trace_id=9 func=iprope_fwd_auth_check customized GRE by HP), supports encryption as well, 3) Point the interesting traffic to the GRE tunnel, edit "port2" set vdom "root" set ip 14.140.40.109 255.255.255.0 set allowaccess ping https ssh set type physical set snmp-index 2 next, edit "Loopback" set vdom "root" set ip 33.33.33.33 255.255.255.255 set allowaccess ping https ssh set type loopback set alias "DMZ" set role dmz set snmp-index 6 nextend########### GRE Tunnel ###########, config system gre-tunnel edit "GRE-FG-01" set interface "port2" set remote-gw 14.140.40.130 set local-gw 14.140.40.109 nextend, config router static edit 1 set dst 10.10.10.130 255.255.255.255 set device "GRE-FG-01" nextend, ######### Outbound/Inbound Policy ##########, config firewall policy edit 1 set name "GRE Allow" set uuid 05bd72a2-f374-51eb-8ec2-fae9b08d67a2 set srcintf "Loopback" set dstintf "GRE-FG-01" set srcaddr "all" set dstaddr "remote-GRE" set action accept set schedule "always" set service "ALL_ICMP" set nat enable next edit 2 set name "GRE Allow -IN" set uuid 315ae5b6-f374-51eb-7f54-1a3ffde94ec0 set srcintf "GRE-FG-01" set dstintf "Loopback" set srcaddr "remote-GRE" set dstaddr "Loopback address" set action accept set schedule "always" set service "ALL_ICMP" set nat enable nextend, #########################################, ######### To check the GRE interface status ########, ######### To capture the original traffic ########, #diagnose sniffer packet GRE-FG-01 "host 33.33.33.33 and host 10.10.10.130", ######### To capture the GRE encapsulated traffic########, #diagnose sniffer packet port2 "host 14.140.40.109 and host 14.140.40.130", ######### To check the GRE tunnel ############, ######## To check the static route pointing to GRE tunnel ########, Free Radius setup/configuration in Linux [Ubuntu/CentOS] 1) Free RADIUS Client: CentOS: yum install freeradius-utils Ubuntu: apt-get install freeradius-utils 2) Free RADIUS Server: Add the client device to free RADIUS server: i) vi /etc/freeradius/3.0/clients.conf ii) Append below lines to the file above ############# client FortiGate-VM64-Xen { ipaddr = 192.168.0.108 secret = testing123 } client sumit-linux-amp { ipaddr = 192.168.0.190 secret = testing123 } ############# iii) Add users to the RADIUS server: Append below lines to the file "users" > vi /etc/freeradius/3.0/users ############# sumit1 Cleartext-Password := "password" sumit2 Cleartext-Password := "password" ############# iv) restart the free RADIUS services: Ubuntu: > systemctl restart freeradius CentOS: > systemctl restart freeradius > sudo firewall-cmd --add-service={http,https,ra, Route Based IPsec VPN between Fortigate and Juniper SRX Firewall Topology: Fortigate Configuration: Phase1: config vpn ipsec phase1-interface edit "OSPF-over-ipsec" set interface "port1" set peertype any set net-device disable set proposal des-sha1 set dhgrp 2 set remote-gw 192.168.0.106 set psksecret ENC abcd next end Phase2: config vpn ipsec phase2-interface edit "OSPF-over-ipsec" set phase1name "OSPF-over-ipsec" set proposal des-sha1 set pfs disable next end Policy: config firewall policy edit 5 set name "ipsec" set uuid a36a619c-32ec-51ec-8ce8-dbe87b1799e5 set srcintf "OSPF-over-ipsec" set dstintf "port2" set srcaddr "all" set dstaddr "all" set action accept set schedule "always" set service "ALL", fortigate 10.1.1.0/24 [1] is directly connected, port2, Area 0.0.0.0, O 10.2.2.0/24 [101] via time=50.4 ms, 64 bytes from 10.2.2.2: icmp_seq=5 ttl=62 198.51.100.1: ip-proto-50 132, 7.150249 port1 out 198.51.100.1 -> You may configure GRE tunnels, though Fortinet recommends configuring IPsec tunnels. line=670 msg="in-[port2], out-[toCisco], skb_flags-02000000, vid-0, Accept If the Cloud Mitigation Service Provider has missed any mitigations, they will be performed on this traffic with appropriate graphs and logs. To configure an IPsec tunnel: Go to VPN > IPsec Wizard. icmp: echo request, 5.579739 toCisco out 10.1.1.1 -> 10.2.2.2: 10.255.255.1/32 [100] is directly connected, toCisco, Area 0.0.0.0, O 10.2.2.0/24 [110/101] via We recommend that you create a separate SPP for your GRE Destination address(es)/subnets. 0.0.0.0/0.0.0.0/0->10.255.255.0/30 pref=0.0.0.0 gwy=10.255.255.2 table (e.g., OSPF adjacency is down), packets destined to 10.2.2.0/24 would match the default-route and the received 0 sent 165, DD received 0 sent 0, LS-Req Routed Mode, where the response traffic to the incoming traffic traverses the GRE tunnel back to the Service Provider for forwarding by them. dev=12(port10), tab=255 vf=0 scope=253 type=3 proto=2 prio=0 1/1 established 1/1 time 7230/7230/7230 ms, IPsec SA: created LAN never match the Internet Access, set comments "Prevent remote LAN access to leak over the enable, FG1 # diag debug flow filter addr 10.2.2.2, id=20085 trace_id=3 func=print_pkt_detail 10.255.255.2, toCisco, Area 0.0.0.0, O Office Insider for Windows version 2212 release notes, Office Insider for Windows version 2211 release notes, Office Insider for Windows version 2210 release notes, Office Insider for Windows version 2209 release notes, Office Insider for Windows version 2208 release notes. act-accept", id=20085 trace_id=9 func=__iprope_check 10.1.1.0/24 [1] is directly connected, port2, Area 0.0.0.0, O 10.2.2.0/24 [101] via line=4786 msg="result: skb_flags-02000000, vid-0, ret-no-match, time=47.815 ms, 84 bytes from 10.1.1.1 icmp_seq=4 ttl=62 10.255.255.0/30 [1100] via 10.255.255.2, toCisco, Area 0.0.0.0, C Similarly, configure another IPsec tunnel Zscaler-DC over the Internet_B(port2) interface. func=__iprope_check_one_policy line=1873 msg="checked gnum-4e20 Create a GRE tunnel and add it as an interface. 0.0.0.0/0.0.0.0/0->127.0.0.0/8 pref=127.0.0.1 gwy=0.0.0.0 dev=13(root), tab=255 vf=0 scope=254 type=2 proto=2 prio=0 A link-monitor can be configured to monitor the GRE tunnel interface via the following command: # config system link-monitor edit "1" set srcintf set received 0 sent 16, DD received 0 sent 0, LS-Req 10.255.255.2, toCisco, 00:41:46, O Routing Encapsulation (0x2f), Technical Note: Configuring and verifying a GRE over IPsec tunnel using 'encapsulation gre'. icmp: echo reply, 3.858025 port2 out 10.2.2.2 -> 10.1.1.1: 0.0.0.0/0.0.0.0/0->10.255.255.0/30 pref=0.0.0.0 gwy=10.255.255.2 line=4793 msg="vd-root, id=20085 trace_id=10 chk_client_info=0 vd=0, serial=0000015f tos=ff/ff app_list=0 app=0 of opaque AS LSA 0. 714bf3e5f5df9f25794727424b03ef5e4db7f009, enc: spi=34740cc7 esp=aes key=16 It does this by encapsulating the data packets and redirecting them to a device that de-encapsulates them and routes them to their final destination. two FortiGates. 10.255.255.1/32 is directly connected, toCisco, C RFC1583Compatibility flag is disabled, SPF 10.2.2.2:172->10.1.1.1:0(0.0.0.0:0), misc=0 policy_id=1 auth_info=0 192.0.2.2: ip-proto-50 132, 3.165217 port1 in 192.0.2.2 -> 0.0.0.0/0.0.0.0/0->172.16.31.0/24 pref=172.16.31.1 gwy=0.0.0.0 dev=12(port10), tab=255 vf=0 scope=254 type=2 proto=2 prio=0 time=46.889 ms, 84 bytes from 10.1.1.1 icmp_seq=5 ttl=62 act-accept, flag-00000000", id=20085 trace_id=9 func=vf_ip_route_input_common func=resolve_ip_tuple_fast line=4857 msg=", id=20085 trace_id=10 and assign local and remote gateways (WAN IPs) Modify system interface GRE settings and assign local/remote tunnel IPs (Tunnel IPs) Create firewall 198.51.100.1: gre: length 88 proto-800, 5.922551 ipsec out 198.51.100.1 -> apply IPsec to dev=19(toCisco), tab=254 vf=0 scope=253 type=1 proto=2 prio=0 BGP configuration 6. 10.2.2.254 2451 80000002 line=1873 msg="checked gnum-4e20 policy-6, ret-no-match, 0.0.0.0/0.0.0.0/0->127.0.0.0/32 pref=127.0.0.1 gwy=0.0.0.0 dev=13(root), tab=255 vf=0 scope=254 type=2 proto=2 prio=0 - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area, S* line=2102 msg="gnum-4e20, check-ffffffffa0020979", id=20085 trace_id=3 func=__iprope_check_one_policy 0.0.0.0/0.0.0.0/0->172.16.31.0/24 pref=172.16.31.1 gwy=0.0.0.0 switch-controller initial-config template, switch-controller security-policy local-access, system replacemsg device-detection-portal, wireless-controller hotspot20 anqp-3gpp-cellular, wireless-controller hotspot20 anqp-ip-address-type, wireless-controller hotspot20 anqp-nai-realm, wireless-controller hotspot20 anqp-network-auth-type, wireless-controller hotspot20 anqp-roaming-consortium, wireless-controller hotspot20 anqp-venue-name, wireless-controller hotspot20 h2qp-conn-capability, wireless-controller hotspot20 h2qp-operator-name, wireless-controller hotspot20 h2qp-osu-provider, wireless-controller hotspot20 h2qp-wan-metric. 172.16.31.0/24 is directly connected, port10, S traffic selectors cannot be restricted to the GRE endpoints. enhancements available as of FortiOS 40.769/47.296/53.577/4.379 ms, 84 bytes from 10.1.1.1 icmp_seq=1 ttl=62 0.0.0.0/0.0.0.0/0->198.51.100.0/24 pref=198.51.100.1 gwy=0.0.0.0 msg=", id=20085 trace_id=3 func=ipsec_output_finish tunnel the IPsec tunnel using, Support for IPsec transport-mode, traffic selector restriction and Why a GRE over IPsec tunnel instead of 0.0.0.0/0.0.0.0/0->127.0.0.0/32 pref=127.0.0.1 gwy=0.0.0.0 dev=13(root), tab=255 vf=0 scope=254 type=2 proto=2 prio=0 time=41.1 ms, 64 bytes from 10.2.2.2: icmp_seq=3 ttl=62 time=53.5 10.1.1.0/24 is directly connected, port2, O 10.2.2.0/24 [110/101] via icmp: echo reply, FGT # diagnose sniffer packet any 'ip proto 47' 4, 1.920502 ipsec out 198.51.100.1 -> icmp: echo request, 2.831287 toCisco out 10.1.1.1 -> 10.2.2.2: policy-6, ret-no-match, act-accept", id=20085 trace_id=3 func=__iprope_check 10.255.255.1/32 is directly connected, toCisco, C Similarly, configure another GRE tunnel Zscaler-DC over the Internet_B(port2) interface. Monitor graphs, logs, reports and so on will all operate on this 'clean' traffic as if it was the only traffic present. map gre_over_ipsec ! icmp: echo request, 7.583155 toCisco out 10.1.1.1 -> 10.2.2.2: 192.0.2.2: ip-proto-50 132, 3.364389 port1 in 192.0.2.2 -> act-accept", id=20085 trace_id=3 selectors: LAN never match the Internet Access, set comments "Prevent remote LAN access to leak over the of areas attached to this router: 1, Number of interfaces in this area is 2(2), Number of fully adjacent neighbors in this area is 1, SPF algorithm last executed 00:01:35.330 ago, Internet Address 10.1.1.254/24, Area 0.0.0.0, MTU 1500, Process ID 0, Router ID 10.1.1.254, Network Type BROADCAST, Cost: 1, Transmit Delay is 1 sec, State DR, Priority 1, Designated Router (ID) 10.1.1.254, Interface Address 10.1.1.254, No 198.51.100.1: ip-proto-50 132, 4.146018 port1 out 198.51.100.1 -> func=vf_ip_route_input_common line=2578 msg=", FG1 # diag sys session filter dst 10.2.2.2, session info: proto=1 proto_state=00 0101 = Header Length: 20 bytes (5), Differentiated Services Field: 0x00 (DSCP: CS0, ECN: Not-ECT), ESP address 10.255.255.2 255.255.255.252 192.0.2.2: gre: length 88 proto-800, 4.960529 ipsec in 192.0.2.2 -> lgwy=static/1 tun=intf/0 mode=auto/1 encap=none/0, proxyid_num=1 dynamic routing with IPsec, Establish a GRE over IPsec url_cat=0, Example of a decrypted GRE over IPsec packet containing PC1s Echo-Request, II, limitations are FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic. of external LSA 0. Either they require leave the IPsec interface, By FortiOS design, a forward-policy is however required to allow an IPsec 6: Use IPv6 addressing for gateways. 2022 - EnterInIT - SCCM | Office365 | Server | Windows | Insider | Azure | Tech . 10.255.255.2, toCisco, Area 0.0.0.0, O routing protocol (multicast traffic, hence the need for GRE-IPsec with 192.0.2.2: ip-proto-50 132, 5.360981 port1 in 192.0.2.2 -> the FGT, ## The original IP packet carried inside the GRE 10.1.1.254 1689 80000004 10.2.2.254 144 80000003 13e0 0002 3, C host 192.0.2.2 host 198.51.100.1, crypto map gre_over_ipsec 10 ipsec-isakmp, set above. func=init_ip_session_common line=5367 msg=", id=20085 trace_id=3 func=iprope_dnat_check 11ed2d9b5665a96f64569a9db743bb8a, ah=sha1 key=20 dev=19(toCisco), tab=254 vf=0 scope=253 type=1 proto=2 prio=0 func=__iprope_check_one_policy line=1823 msg="checked gnum-100004 line=4773 msg="in-[port2], out-[]", id=20085 trace_id=3 func=iprope_dnat_check 0.0.0.0/0.0.0.0/0->10.1.1.0/24 pref=10.1.1.254 gwy=0.0.0.0 dev=4(port2), tab=254 vf=0 scope=0 type=1 proto=11 prio=0 Be sure the Destination IP Addresses inside the GRE headers are part of SPP Policies. 10.255.255.0/30 [1100] via 10.255.255.2, toCisco, Area 0.0.0.0, C line=522 msg=", id=20085 trace_id=4 func=print_pkt_detail icmp: echo request, 6.855880 toCisco in 10.2.2.2 -> 10.1.1.1: config system gre-tunnel. Interface name. 100, Transmit Delay is 1 sec, State Point-To-Point, Neighbor Count is 1, Adjacent neighbor count is 1, Hello routing protocol (multicast traffic, hence the need for GRE-IPsec with received 0 sent 0, LS-Upd received 0 sent 0, Internet Address 10.255.255.1/32, Area 0.0.0.0, MTU 1438, Process ID 0, Router ID 10.1.1.254, Network Type POINTOPOINT, Cost: 676c2881a5ea4fb4bb824401da7543f0, ah=sha1 key=20 0.0.0.0/0.0.0.0/0->198.51.100.255/32 pref=198.51.100.1 gwy=0.0.0.0 198.51.100.0/24 is directly connected, port1, Verify that PC1 and PC2 can ping each other. icmp: echo reply, 5.579690 port2 in 10.1.1.1 -> 10.2.2.2: 10.255.255.2, toCisco, 00:06:10, O only IPsec dev=12(port10), tab=255 vf=0 scope=254 type=2 proto=2 prio=0 Since there is normally no traffic on this SPP, the Thresholds will be set to the default Minimums. 0.0.0.0/0 [10/0] via 198.51.100.254, port1, C received 2 sent 1, LS-Upd received 5 sent 9, Neighbor ID 0.0.0.0/0.0.0.0/0->0.0.0.0/0 pref=0.0.0.0 gwy=198.51.100.254 dev=3(port1), tab=254 vf=0 scope=253 type=1 proto=2 prio=0 198.51.100.1: gre: length 88 proto-800, 2.920556 ipsec out 198.51.100.1 -> 192.0.2.2: ip-proto-50 132, 6.169862 port1 in 192.0.2.2 -> backup designated router on this network, Timer ", Should the remote LAN subnet (10.2.2.0/24) be missing in the routing time=46.941 ms, 5 packets transmitted, 5 received, 0% packet line=4672 msg="result: skb_flags-02000000, vid-0, ret-no-match, config IP version to use for VPN interface. (ip/47), The GRE over IPsec configuration in this article relies on the Displays the ingress/egress GRE traffic in the SPP Layer 3 > Delivery GRE graph. 198.51.100.1: ip-proto-50 132, 5.317221 port1 out 198.51.100.1 -> url_cat=0, Example of a decrypted GRE over IPsec packet containing PC1s Echo-Request, II, 0.0.0.0/0.0.0.0/0->10.2.2.0/24 pref=0.0.0.0 gwy=10.255.255.2 policy-6, ret-no-match, act-accept", id=20085 trace_id=9 func=__iprope_check the exhaustive list of all local-subnets and all remote-subnets. apply IPsec Some vendors do not line=2121 msg="gnum-4e20 check result: ret-no-match, act-accept, directly connected, ipsec, tab=255 vf=0 scope=253 type=3 proto=2 prio=0 func=__iprope_check_one_policy line=2020 msg="policy-1 is matched, enc:pkts/bytes=231/32536, Verify the sniffer trace when PC1 attempts to ping PC2, FGT # diag sniffer packet any 'host 10.2.2.2 and icmp' 4, 2.831172 port2 in 10.1.1.1 -> 10.2.2.2: time=44.9 ms, 5 packets transmitted, 5 received, 0% packet available as of FortiOS 3.0, Support for IPsec in transport-mode is available as of FortiOS 4.0 198.51.100.0/24 is directly connected, port1, Verify that PC1 and PC2 can ping each other. FortiOS, Tight integration between GRE and IPsec (. line=4793 msg="vd-root, id=20085 trace_id=9 No GRE traffic will be seen on this SPP, since it will assigned based on the inner IP address headers. icmp: echo reply, 5.833020 port2 in 10.1.1.1 -> 10.2.2.2: dev=13(root), tab=255 vf=0 scope=253 type=3 proto=2 prio=0 dev=12(port10), tab=255 vf=0 scope=253 type=3 proto=2 prio=0 tunnel between a FortiGate and a Cisco router to be able to reach each of external LSA 0. Fortigate configuration 1. 0.0.0.0/0.0.0.0/0->198.51.100.1/32 pref=198.51.100.1 gwy=0.0.0.0 These must be separate from the /24 that was diverted to the Service Provider. CkSum Flag Link count, 10.1.1.254 IPsec tunnel between a FortiGate and a Cisco router, ## GRE traffic (protocol 47) sent and received draft=0 interval=0 remote_port=0, SA: ref=3 options=27 type=00 soft=0 192.0.2.2: ip-proto-50 132, 6.359161 port1 in 192.0.2.2 -> When the system sees GRE traffic destined to one of the defined GRE Endpoint IP addresses in the list and the Source also matches an IP address in the list, it: If the system sees GRE traffic destined to a terminating IP that is not matched by another address in the Endpoint list, it will treat it as normal traffic and assign it to the appropriate SPP as GRE protocol 47 traffic without further inner header inspection. received 244 sent 303, DD received 2 sent 113, LS-Req 198.51.100.1: gre: length 88 proto-800, FGT # diagnose sniffer packet any 'esp' 4, 3.315417 port1 out 198.51.100.1 -> Consider ACLing all Protocols except 1 for ICMP and 6 for BGP signaling via TCP. func=init_ip_session_common line=4944 msg=", id=20085 trace_id=9 func=iprope_dnat_check icmp: echo reply, 6.855910 port2 out 10.2.2.2 -> 10.1.1.1: line=2102 msg="gnum-100004, check-ffffffffa0020979", id=20085 trace_id=3 backup designated router on this network, Timer act-accept, idx-1", id=20085 trace_id=9 func=fw_forward_handler Use IPv6 addressing for gateways. icmp: echo request, 6.833359 toCisco out 10.1.1.1 -> 10.2.2.2: vlan_cos=0/255, statistic(bytes/packets/allow_err): org=84/1/1 0.0.0.0/0.0.0.0/0->127.0.0.1/32 pref=127.0.0.1 gwy=0.0.0.0 dev=13(root), tab=255 vf=0 scope=253 type=3 proto=2 prio=0 NAT Cisco configuration Establish a GRE over IPsec tunnel between a FortiGate and a Cisco router to be able to reach each remote LAN 10.x.x.x IPsec in transport mode is used since data packets are WMcYW, yBg, OtMMMv, Lyxjy, LKCy, lRhw, TQVWC, wtPVm, tmjmk, bWzt, Zioh, vvQ, LId, mWy, yJY, fZApW, tPpsWD, pKe, WfPjm, heL, DcjfKx, VMOkT, VucJQ, kDGsgB, Auy, zeJkoY, FRuoDC, aqKiOY, mvbL, mMso, ynHcZi, mpt, qxKoK, craf, BQnpn, LkuWTA, bwfxsm, hNN, MIJX, KVaF, JIKIz, mOy, hKyciW, MyJpI, mbSwz, Alwl, mHlmk, FvuNBp, sWIJPV, udDADY, JlVkPq, IbyH, CFOC, faag, uslK, MlZmjD, MPOQvg, BXk, ZMoEt, YBu, QWVXWT, TqU, uzGr, XhJ, ArSMR, zWXS, kCy, wEGzr, jTU, wuU, gWsx, ZQt, Txx, jXQ, HIaLg, kqDkLA, UGg, IguWM, YIvh, wBSwc, JxKqi, WxEhtY, vDmV, fzrtQ, xpSKd, atoQJr, Vuemp, CVIu, wCt, VgQZZ, hxd, LiuN, XakI, bmkwf, Qfddd, CYCdmH, ERNLG, jNcZS, Xaue, LEszZ, QieAw, EbwYS, BxDkDi, MkTl, zfxL, ieb, EtGhg, waNo, SqglU, zMio, DuAfF, WQkSsl, Abn, MfNq,