Overlay tunnels reduce the maximum transmission unit (MTU) of an interface by 20 octets (assuming that the basic IPv4 packet This is The tunnels are not tied to a specific passenger Tunnel group name must match what the peer will send as its IKEv1 or IKEv2 identity. Four Steps to Fully Configure Cisco DMVPN To help simplify the configuration of DMVPN we've split the process into 4 easy-to-follow steps. L2 EoGRE is not supported on the Cisco CSR1000V platform. interface MTU after the VTI is enabled, you must Virtual Ethernet interface does not support encapsulation untagged. An account on Cisco.com is not required. In the IKEv1 IPsec Proposals (Transform Sets) panel, click Add. layer and to transport IPv6 packets in IPv6 tunnels and IPv4 packets in IPv6 tunnels. In order to configure a GRE tunnel on a router, refer How to configure a GRE tunnel. Configure the remote peer with identical IPsec proposal To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. You If you think, that the router may be under heavy load, you can avoid looping traffic for router, if you add the direct connection from ASA to inside LAN (to Core Switch). All rights reserved. Route Tracking in the ASA General Operations Configuration Guide in http://www.cisco.com/go/asa-config. To create a new VTI interface and establish a VTI tunnel, perform the following steps: Implement IP SLA to ensure that the tunnel remains up when a router in the active tunnel is unavailable. IPSec is configured on the ASA (which works fine) and the GRE Tunnel terminates on the router behind. Cisco Modeling Labs - Personal; Community Impact; . Follow these steps to configure GRE Tunnel IP Source and Destination VRF Membership: Procedure Configuration Example for GRE Tunnel IP Source and Destination VRF Membership In this example, packets received on interface e0 using VRF green are forwarded out of the tunnel through interface e1 using VRF blue. The diagram below shows a point-to-point GRE VPN network. or just the IPv6 protocol stack. The following sections provide information about configuring IPv6 over IPv4 GRE tunnels: Overlay tunneling encapsulates IPv6 packets in IPv4 packets for delivery across an IPv4 infrastructure (a core network or The edge devices and the end systems must be dual-stack implementations. ASDM Book 2: Cisco Secure Firewall ASA Series Firewall ASDM Configuration Guide, 7.19. If you will be migrating configurations from other devices to ASA 5506 devices, use the tunnel ID range of 1 - 100. (Optional) Check the Enable security association lifetime check box, and enter the security association duration values in kilobytes and seconds. VTI tunnels are always up. tunnels is that broadcasts are not flooded through the tunnel, so there is less wasted bandwidth and less load on the managed devices.The forwarding method for a Layer-3 GRE Generic Routing Encapsulation. The ASA supports a logical interface called Virtual Tunnel Interface (VTI). This allows dynamic or static routes to be used. VTI and crypto map configurations can co-exist on the same physical interface, provided the peer address configured in the But I would wait some releases until changing to 9.7 in production. tunnel An IPsec profile contains the required security protocols and algorithms in the IPsec proposal or transform set that it references. This is to facilitate successful rekeying by the initiator end and ensure that the tunnels remain This new VTI can be used to create It has been attached to the OUTSIDE interface. Up to 100 VTI interfaces are supported. I am not familiar with any firewall capabilities of Cisco routers but I believe these won't be able to cover the capabilities of ASA. All rights reserved. This ensures that You can use either pre-shared key or certificates for authenticating the IKE session associated with a VTI. You can choose either an IKEv1 transform set or an IKEv2 IPsec proposal. If ASA is terminating IOS IKEv2 VTI clients, disable the config-exchange request on IOS, because ASA cannot retrieve the mode-CFG That means, ISP was connected to the router, inside LAN was separated from router by ASA: But ispite of this fact, there was no problem to terminate IPsec on ASA and GRE on Router. interface-number }. crypto map and the tunnel destination for the VTI are different. Sorry about the NAT command. BGP adjacency is re-established with the new active peer. [eui-64 ]. More powerful in Firewalling only, the routers Rule when it comes to routing capabilities. With GRE, a virtual tunnel is created between the two endpoints (Cisco routers) and packets . ipv6 ASAs do not support the termination of GRE tunnels. This is why people are dropping their ASA's, It is just stupid. Chapter Title. And ASA sends filtered payload directly to LAN, avoiding passing it back to router. You would have to use a router in order to use GRE tunnels. tunnel I had a configuration, where ASA was behind the router. header does not contain optional fields). I see that you have 2 interfaces, namely inside and outside and have got one access-list named "gre" applied via the command : Can you please apply the following capturescap asp type asp-drop alland after few minutes , run the commandshow cap asp | in10.0.1.1orshow cap asp | in10.0.2.1The latter output will show if there are any drops on the ASA. Also, the Tunnel Interfaces will be using as actual source IPs the addresses of the outside router interfaces (20.20.20.1 for R1 and 50.50.50.1 for R2). Configure the ASA 5506-X interfaces. This feature can give you similar capabilities as ASA in many cases, but a bit complicated in configuration. Then you need to specify the source and destination of the GRE tunnel. New here? having static VTI which supports route based VPN with dynamic routing protocol also satisfies many requirements of a virtual multipoint | gre Perfect Forward Secrecy (PFS) generates a unique session key for each encrypted exchange. cap asp type asp-drop all" and "show cap asp | in10.0.1.1" on the Firewall but nothing showed up. This behavior does not apply to logical VTI interfaces. for the VTI. Explained As Simple As Possible. These features are available in all the releases subsequent to the one they were introduced in, unless noted otherwise. Create IPSec profile to connect previously defined ISAKMP and IPsec configs together. Access list can be applied on a VTI interface to control traffic through VTI. Here, we used Interface name. gre Find answers to your questions by entering keywords or phrases in the Search bar above. Mobile nodes access the Internet over Wi-Fi access points (APs). As an alternative to policy based VPN, a VPN tunnel or IPv6 as the transport protocol. IPv6 traffic can be carried over IPv4 GRE tunnels using the standard GRE tunneling technique that is designed to provide the services to implement any standard point-to-point encapsulation scheme. Deployments become easier, and or configure an infinite IPsec lifetime value in the responder-only end to prevent expiry. Restrictions for Layer 2 Ethernet over GRE Transport on IPv6 is not supported. All Services > Local Security Gateway > Create Local Security Gateway > Name it > Supply the public IP > Supply the Subnet (s) 'behind' the ASA > Select your Resource Group > Create. Then Router decapsulated payload from GRE headers. Find answers to your questions by entering keywords or phrases in the Search bar above. Find answers to your questions by entering keywords or phrases in the Search bar above. To configure the basic settings: Log in to the ASA 5506-X with ASDM. Additionally, you can configure keepalive via the command: Router# configure terminalRouter(config)#interface tunnel0Router(config-if)#keepalive 5 4. and then run "debug tunnel keepalive" to see on which side you are having issues with GRE traffic. First of all, Cisco routers are capable of firewall services. interface can have either IPv4 or IPv6 addresses assigned (this is not shown in the task). GRE encapsulation supports the following features: IPv4/IPv6 over GRE IPv4 transport MPLS PoP over GRE IPv4 transport ABF (Access List Based Forwarding) v4/v6 over GRE The sample configuration connects a Cisco ASA device to an Azure route-based VPN gateway. IPv6 supports GRE type of overlay tunneling. Use the Cisco Feature Navigator to find information about platform and software image support. attached to the end of each tunnel. Learn more about how Cisco is using Inclusive Language. From security perspective, it is also ok to connect ASA directly to LAN, because ASA filters all traffic. 06:17 PM. address access-group gre in interface outside Can you please apply the following captures cap asp type asp-drop all and after few minutes , run the command show cap asp | in 10.0.1.1 or show cap asp | in 10.0.2.1 The latter output will show if there are any drops on the ASA. configure Connection Settings. Create and configure a tunnel interface on the R1 Router. Exceptions may be present in the documentation due to language that is hardcoded in the user interfaces of the product software, language used based on RFP documentation, or language that is used by a referenced third-party product. mode Learn more about how Cisco is using Inclusive Language. Thoughts? destination By the way, I saw in release notes of 9.7 version: Virtual Tunnel Interface (VTI) support for ASA VPN module, http://www.cisco.com/c/en/us/td/docs/security/asa/asa97/release/notes/asarn97.html. You must By default, all traffic through VTI is encrypted. Anyway, the GRE tunnel finally worked. - edited 22, 2015 3 likes 9,320 views Download to read offline Technology As you might know, Cisco ASA can not terminate GRE tunnels. By default, the security level for VTI interfaces is 0. The second thought. If you need an end of the VTI tunnel to act only as a responder, check the Responder only check box. This supports route based VPN with IPsec profiles attached to the end of each tunnel. In the General tab, enter the VTI ID. VTIs are only configurable in IPsec mode. prefix-length set, according to the underlying physical Support for GRE over IPsec with ASA 5555-x ? The router where GRE tunnelsterminate runs BGPfor selectionof path to reach the side via one of the GWs. Select the IPsec profile in the Tunnel Protection with IPsec Profile field. If an interface is specified, the interface must be configured with an IPv4 address. To configure a VTI tunnel, create an IPsec proposal (transform set). Using VTI does away with the requirement of configuring static crypto map access lists and mapping them to interfaces. The default IP address is 192.168.1.1. This ensures a secure, logical communication path between two site-to-site VTI VPN peers. To access Cisco Feature Navigator, Generic Routing Encapsulation (GRE) is a tunnelling protocol which is used to transport IP packets over a network .Developed by Cisco Systems that can encapsulate a wide variety of network layer protocols inside virtual point-to-point links over an Internet Protocol network. For complete syntax and usage information for the commands used in this chapter. To configure the tunnel source and destination, issue the tunnel source {ip-address | interface-type} and tunnel destination {host-name | ip-address} commands under the interface configuration mode for the tunnel. The documentation set for this product strives to use bias-free language. So there was a possibility to control decapsulated traffic with ASA's firewall capabilities. Use these resources to familiarize yourself with the community: How to let a GRE tunnel pass through ASA Firewall ? GRE Tunnel Configuration on Cisco Packet Tracer Watch on GRE Tunnel Configuration In Router 0, we will create the Tunnel interface and then give this interface an IP Address. terminal, interface GRE tunnels are supported on Cisco IOS Routers. This supports route based VPN with IPsec profiles If the rekey configuration in the initiator end is unknown, remove the responder-only mode to make the SA establishment bi-directional, (Optional) Check the PFS Settings check box to enable PFS, and select the required Diffie-Hellman Group. or between an edge device and an end system. For information about how to configure interfaces, see the Cisco ASA 5506-X documentation. My deployment requires use of 2ASAs for VPN tunnel redundancy where each ASA forms a VPN tunnelwith a remote VPN device via different ISP and carries GRE tunnel inside each VPN tunnel. (Optional) Check the Enable sending certificate check box, and select a Trustpoint that defines the certificate to be used while initiating a VTI tunnel connection. Wireshark captures show that GRE packets arrive at the ASA on the inside interface but dont leave on the outside interface. By using overlay tunnels, you can communicate with isolated IPv6 networks without upgrading the IPv4 infrastructure {host-name | ip-address | ipv6-address }. and IPsec profile parameters. no longer have to track all remote subnets and include them in the crypto map access list. As in IPv6 manually configured tunnels, GRE tunnels are links between two points, with a separate tunnel for each link. Sure, that traffic passes ASA twice, but, as I already mentioned, throughput of ASA is usually high, so it won't be a problem. In the IPsec Proposals (Transform Sets) main panel, click Apply. What do they mean ? Choose Configuration > Site-to-Site VPN > Advanced > IPsec Proposals (Transform Sets). If you plan is just to have a route-based IPsec VPN in the future, this could be the way to go. For the purposes of this documentation set, bias-free is defined as language that does not imply discrimination based on age, disability, gender, racial identity, ethnic identity, sexual orientation, socioeconomic status, and intersectionality. For IKEv1 in LAN-to-LAN tunnel groups, you can use names which are not IP addresses, if the tunnel authentication method is But the newest ASA software has IPsec-tunnel-interfaces. Additionally, you can configure keepalive via the command: Overlay tunnels can be configured between border devices or between a border device and a host; however, both {ip-address | ipv6-address | interface-type I used to translate the private IP to a Public one but it didn't change anything so forget about it. 04:40 PM Your other solution sounds plausible to me, however I am concernedof the performance penalty it will incur due to extra loop involved for all traffic. Generic Routing Encapsulation (GRE) is a tunneling protocol that provides a simple generic approach to transport packets of one protocol over another protocol by means of encapsulation. Customers Also Viewed These Support Documents, #GRE #ASA #Router_Behind_Firewall #VLAN #VLAN_over_WAN. Choose Add > VTI Interface. You can do GRE over IPsec tunnels with a router as the GRE endpoint and ASA as the IPsec endpoint or a router as both GRE and IPsec endpoint. have matching Diffie-Hellman groups on both peers. GRE tunnels are not configurable on the ASA in any version. For additional help regarding GRE tunnels, refer to Configuration Examples and TechNotes. As already mentioned, there is no GRE-tunnel. Apply IPSec encryption to tunnel interface at both routers Solution Configure Router R1 for GRE. private cloud. configure 1000 encapsulation tunnels or 64 decapsulation tunnels. This table provides release and related information for the features explained in this module. tunnels should be considered as a transition technique toward a network that supports both the IPv4 and IPv6 protocol stacks Sorry, Karsten has already mentioned that. Note. Select ESP Encryption and ESP Authentication. How to configure a Generic Routing Encapsulation (GRE) tunnel on the Adaptive Security Appliance (AS Customers Also Viewed These Support Documents, How to configure a Generic Routing Encapsulation (GRE) tunnel on the Adaptive Security Appliance (ASA). The use of overlay I had a configuration, where ASA was behind the router. Prerequisites Requirements Ensure that you meet these requirements before you attempt this configuration: disable and reenable the VTI to use the new MTU The ASA is not relevant anymore and everyone is stuck with it. IP Addressing Services Configuration Guide, Cisco IOS XE Cupertino 17.7.x (Catalyst 9400 Switches), View with Adobe Reader on a variety of devices, View in various apps on iPhone, iPad, Android, Sony Reader, or Windows Phone, View on Kindle device or Kindle app on multiple devices. This can be any value from 0 to 10413. The key derivation algorithms generate IPsec security association (SA) keys. So, let's configure the GRE Tunnel. Configuring GRE Tunnel Through a Cisco ASA Firewall May. PDF - Complete Book (17.04 MB) PDF - This Chapter (1.97 MB) View with Adobe Reader on a variety of devices profile in the initiator end. Do Cisco ASA 5555-x supports GRE tunnel ? GRE usages IP protocol number 47. can be created between peers with Virtual Tunnel Interfaces configured. Plus, I ran the command "debug tunnel keepalive" on both routers and this showed up : Intra-2#*Mar 17 10:04:20.579: Tunnel1: sending keepalive, 10.0.1.1->10.0.2.1 (len=24 ttl=255), counter=25Intra-2#*Mar 17 10:04:25.579: Tunnel1: sending keepalive, 10.0.1.1->10.0.2.1 (len=24 ttl=255), counter=26Intra-2#*Mar 17 10:04:30.579: Tunnel1: sending keepalive, 10.0.1.1->10.0.2.1 (len=24 ttl=255), counter=27Intra-2#*Mar 17 10:04:35.579: Tunnel1: sending keepalive, 10.0.1.1->10.0.2.1 (len=24 ttl=255), counter=28Intra-2#*Mar 17 10:04:40.579: Tunnel1: sending keepalive, 10.0.1.1->10.0.2.1 (len=24 ttl=255), counter=29, Intra-1#*Mar 17 10:03:29.467: Tunnel1: sending keepalive, 10.0.2.1->10.0.1.1 (len=24 ttl=255), counter=16Intra-1#*Mar 17 10:03:34.467: Tunnel1: sending keepalive, 10.0.2.1->10.0.1.1 (len=24 ttl=255), counter=17Intra-1#*Mar 17 10:03:39.467: Tunnel1: sending keepalive, 10.0.2.1->10.0.1.1 (len=24 ttl=255), counter=18Intra-1#*Mar 17 10:03:44.467: Tunnel1: sending keepalive, 10.0.2.1->10.0.1.1 (len=24 ttl=255), counter=19Intra-1#*Mar 17 10:03:49.471: Tunnel1: sending keepalive, 10.0.2.1->10.0.1.1 (len=24 ttl=255), counter=20. Also with this device, is it possible to create GRE interfaces ? (To represent your Cisco ASA). A network that uses overlay tunnels is difficult to troubleshoot. 2022 Cisco and/or its affiliates. tunnel-number. Specifies the source IPv4 address or the source interface type and number for the tunnel interface. Each GRE is an IP encapsulation protocol that is used to transport packets over a network. Perform this task to configure a GRE tunnel on an IPv6 network. Finally create the VPN > Select your Virtual Network Gateway > Connections > Add. the figure below). This feature can give you similar capabilities as ASA in many cases, but a bit complicated in configuration. A larger modulus provides higher security, but requires more processing time. IPv6 traffic can be carried over IPv4 GRE tunnels using the standard GRE tunneling technique that is designed to provide Choose Configuration > Device Setup > Interface Settings > Interfaces. Egressing traffic from the VTI is encrypted In order to configure a GRE tunnel on a router, refer How to configure a GRE tunnel. tunnels that connect isolated IPv6 networks should not be considered a final IPv6 network architecture. It will need an IP address, (here I'm using 10.0.0.1/30). Full Access to our 750 Lessons. 03-08-2019 This allows dynamic or static routes to be used. GRE tunnels can be configured to run over an IPv6 network You can use the following command to enable IPsec traffic through the ASA without checking ACLs: hostname(config)# sysopt connection permit-vpn. Enter the source IP Address of the tunnel and the Subnet Mask. I permit all traffic from inside as well from the outside. Please, see the attach. GRE encapsulates a payload, that is, an inner packet that needs to be delivered to a destination network inside an outer IP packet. The tunnels are not tied to a specific passenger or transport You will need to create an IPsec profile that references The ASA supports a logical interface called Virtual Tunnel Interface (VTI). The primary use of GRE tunnels is for stable connections that require regular secure communication between two edge devices Create a Cisco GRE tunnel Add route to remote LAN reachable via GRE tunnel interface IP Configure ISAKMP (IKE) = (ISAKMP Phase 1) Create a transform set (ISAKMP phase 2 policy), used to protect our data. The MTU for VTIs is automatically go to http://www.cisco.com/go/cfn. IKE and IPsec security associations will be re-keyed continuously regardless of data traffic in the tunnel. For the responder, {aurp | cayman | dvmrp | eon | gre | gre 1. If I place the GRE traffic inside of the IPsec tunnel, is it not secure? The tunnel VTI is a tunnel interface witch can be used in many cases instead of GRE over IPsec. For the purposes of this documentation set, bias-free is defined as language that does not imply discrimination based on age, disability, gender, racial identity, ethnic identity, sexual orientation, socioeconomic status, and intersectionality. interface. To permit any packets that come from Any reference to sample configuration specific to this model. When configuring GRE, a virtual Layer3 " Tunnel Interface " must be created. ASDM Book 3: Cisco ASA Series VPN ASDM Configuration Guide, 7.9, View with Adobe Reader on a variety of devices. In this Cisco DMVPN configuration example we present a Hub and Spoke topology with a central HUB router that acts as a DMVPN server and 2 spoke routers that act as DMVPN clients. Hi I see that on FW 2 ,we are hitting the following nat rules: object network router-staticnat (inside,outside) static 30.30.30.3. which translates 10.0.2.1/47 to 30.30.30.3/47Is this supposed to be there ? Generic Routing Encapsulation (GRE) is a tunneling protocol developed by Cisco that allows the encapsulation of a wide variety of network layer protocols inside point-to-point links.. A GRE tunnel is used when packets need to be sent from one network to another over the Internet or an insecure network. Enhanced IPv6 Neighbor Discovery Cache Management, Information About Configuring IPv6 over IPv4 GRE Tunnels, Configuration Example: Tunnel Destination Address for IPv6 Tunnel, Feature History for IPv6 over IPv4 GRE Tunnels. tunnel endpoints must support both the IPv4 and IPv6 protocol stacks. Although, you can configure the GRE Tunnel over the IPSec VPN for securing the GRE tunnel. authentication under the tunnel group command for both initiator and responder. David Davis has the details . protocol but, in this case, carry IPv6 as the passenger protocol with the GRE as the carrier protocol and IPv4 or IPv6 as Also, VTI tunnel does not give additional overhead from GRE header for VPN traffic. Spoke-to-Spoke traffic must pass through the hub. VTI gives no need of configuring crypto maps. ipv6 | ipip [decapsulate-any ] | iptalk | ipv6 | mpls | nos. the services to implement any standard point-to-point encapsulation scheme. Check the Ensure the Enable Tunnel Mode IPv4 IPsec check box. So Intra1 and Intra2 show that tunnel keepalive/hello messages are being sent out but we do not see packets coming back and as per your ASP captures, it does not look like ASA is dropping them either. For additional help regarding GRE tunnels, refer to Configuration Examples and TechNotes. ipv6-prefix For both IKEv1 and IKEv2, you must configure the pre-shared key under the tunnel group used The responder-only end will not initiate the tunnel Configure IKEv1 or IKEv2 to establish the security association. Using generic routing encapsulation (GRE) tunnels on Cisco routers can come in handy with Cisco router administration, and configuring GRE tunnels is relatively easy. All the routers involved in this tutorial are CISCO1921/K9 Step 1. are links between two points, with a separate tunnel for each link. If you are using IKEv2, set the duration of the security association lifetime greater than the lifetime value in the IPsec The next step is to configure a tunnel group. This chapter describes how to configure a VTI tunnel. SA negotiation will start when all tunnel parameters are configured. These steps are: Configure the DMVPN Hub Configure the DMVPN Spoke (s) Protect the mGRE tunnels with IPSecurity (optional) GRE or IP-in-IP tunnels support 16 unique source addresses. Refer to Configuring Router-to-Router IPSec (Pre-shared Keys) on GRE Tunnel with IOS Firewall and NAT for information on how to configure the basic Cisco IOS Firewall configuration on a GRE tunnel with Network Address Translation (NAT). For certificate based authentication using IKEv1, you must specify the trustpoint to be used at the initiator. Try for Just $1. About Layer-3 GRE Tunnels. The APs are either autonomous or connected to a wireless LAN controller (WLC). For the ASA which is a part of both the VPN VTI domains, and has BGP adjacency on the physical interface: When a state change is triggered due to the interface health check, the routes in the physical interface will be deleted until an IPsec tunnel without checking ACLs for the source and destination interfaces, enter the sysopt connection permit-vpn command or rekeying. attributes for this L2L session initiated by an IOS VTI client. 06-22-2009 This is where we define authentication and the pre-shared-key: Learn any CCNA, CCNP and CCIE R&S Topic. The Add VTI Interface window appears. Later it become industry standard (RFC 1701, RFC 2784, RFC 2890). Usually, ASAs are more powerfull in routing and firewall capabilities, comparing to routers (sure, it depends on concrete models). The IPsec traffic (ike and esp) passed from ISP through Router with no inspection and terminated on ASA. Is there a wayto overcome/workaround this drawback without throwing additional gear to solve the problem? Cisco Network Security Channel - https://www.youtube.com/c/CiscoNetSec/. Book Title. the IPsec proposal, followed by a VTI interface with the IPsec profile. to ensure compatibility of tunnel range of 1 - 100 available in ASA 5506 devices. However, if you change the physical of a configured tunnel must support both the IPv4 and IPv6 protocol stacks. Harris Andrea Follow Network Engineer at Networks Training mode The GRE tunnel will be running between the two Tunnel Interfaces (10.0.0.1 and 10.0.0.2 as shown from diagram). group has a different size modulus. Finally I've changed some MTU settings because typically MTU's are set to 1500 and GRE adds an overhead, I'm dropping the MTU to 1400 and setting the maximum . This unique session key protects in global configuration mode. In order to configure the GRE tunnel, you must need connectivity between two remote routers through static Public IP address. New here? not be hit if you do not have same-security-traffic configured. The benefit of Layer-3 GRE Generic Routing Encapsulation. By default, GRE does not perform any kind of encryption. The Best Dollar You've Ever Spent on Your Cisco Career! IPv6 over IPv4 GRE Tunnels can carry IPv6, Connectionless Network Service (CLNS), Use these resources to familiarize yourself with the community: Customers Also Viewed These Support Documents, cisco-screen_shot_2017-02-13_at_10.46.15_am.png. So, the traffic from remote VPNs will pass through router only at once. All I had to do was assign static routes on the Internet router and add an access list on the Firewalls which permits the IPs of the routers. Specifies the destination IPv6 address or hostname for the tunnel interface. GRE tunnels are supported on Cisco IOS Routers. The sample requires that ASA devices use the IKEv2 policy with access-list-based configurations, not VTI-based. Access control lists can be applied on a VTI interface to control traffic through VTI. Therefore, overlay DHCP relay is not supported on Virtual Tunnel Interfaces (VTIs). So wondering if looping traffic back & forth between ASA & router will have any implication from dynamic routing perspective. Specifies the IPv6 network assigned to the interface and enables IPv6 processing on the interface. IKEv2 allows asymmetric tunnel The documentation set for this product strives to use bias-free language. Then Router directed payload traffic back to ASA. For example, there is a feature, called Zone-based Firewall for Cisco routers. And what should I do ? Regards,Dinesh MoudgilP.S. To terminate GRE tunnels on an ASA is unsupported. you must configure the trustpoint in the tunnel-group command. First of all, Cisco routers are capable of firewall services. To configure PFS, you have to select the Diffie-Hellman key derivation algorithm between them. To configure GRE IPv6 tunnels, perform this procedure: When GRE IPv6 tunnels are configured, IPv6 addresses are assigned to the tunnel source and the tunnel destination. to use when generating the PFS session key. After the updated configuration is loaded, the new VTI appears in the list of interfaces. As in IPv6 manually configured tunnels, GRE tunnels The connection uses a custom IPsec/IKE policy with the UsePolicyBasedTrafficSelectors option, as described in this article.. and many other types of packets. The first step is to configure your firewall device with the appropriate tunnel interfaces. Enter the IKE v1 IPsec Proposal or the IKE v2 IPsec Proposal created for the IPsec profile. Cisco invented GRE, why the hell can they not secure it? Please rate helpful posts. To configure Generic Routing Encapsulation (GRE) over an IPSec tunnel between two routers, perform these steps: Create a tunnel interface (the IP address of tunnel interface on both routers must be in the same subnet), and configure a tunnel source and tunnel destination under tunnel interface configuration, as shown: interface Tunnel0 the status become up and the protocol status is down on both R1 and R3, my objective for this GRE is to able to . To configure this feature, use the same-security-traffic command in global configuration mode with its intra-interface argument. Tags: asa_5500 asa_7.x configuration gre k52019526 vpn 0 Helpful Share LAN <=> Router (BGP+GRE) < > VPN. After that, we we will define the Tunnel Source, with IP Address or with Interface name. Each step is required to be completed before moving to the next one. Configure the Cisco ASA In our example, we configure a Cisco ASA 5506-X. Use these resources to familiarize yourself with the community: Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type. For IKEv2, you must configure the trustpoint to be used for I'm sure there would be FW capabilities in ASA which would be missing in other IOS routers, so we won't be able to offload everything from ASA. setting. Check the Chain check box, if required. See Configure Static up. As an alternative to policy based VPN, a VPN tunnel can be created between peers with Virtual Tunnel Interfaces configured. Consult your VPN device vendor specifications to verify that . Retain the default selection of the Tunnel check box. P.S. When an outside interface and VTI interface have the security level of 0, if you have ACL applied on VTI interface, it will Specifies a tunnel interface and number, and enters interface configuration mode. The tunnel I ran the command "cap asp type asp-drop all" and "show cap asp | in10.0.1.1" on the Firewall but nothing showed up. All the fields need to have valid values or selections for the tunnel to be displayed in the VPN Wizard. You can configure one end of the VTI tunnel to perform only as a responder. This scenario may be usefull, if ASA is equiped with IPS or FirePOWER services. In the Preview CLI Commands dialog box, click Send. / In this case, IPsec traffic will come to ASA, decrypted GRE traffic comes to router, routersends decapsulated payload back to ASA. These RGs or CPE can be configured in bridged mode, and Ethernet over Generic Routing Encapsulation (GRE) tunnels can be used to forward Ethernet traffic to the aggregation device. Configure the HUB router If Network Address Translation has to be applied, the IKE and ESP packets will be encapsulated in the UDP header. Before we begin with the tunnel configuration, we need to make sure no ACL is blocking GRE protocol (47) from the Incapsula Public IP to the Customer Public IP. ipv6 command specifies GRE as the encapsulation protocol for the tunnel. Hopefully, sometimes we will see VTI tunnels on ASA gearstoo. The host or router at each end Command Reference (Catalyst 9400 Series Switches). 2022 Cisco and/or its affiliates. the transport protocol. However, you can pass GRE traffic through a Cisco ASA 5500 firewall as described in this tutorial. digital certificates and/or the peer is configured to use aggressive mode. You can use dynamic or static routes for traffic using the tunnel interface. authentication methods and keys. Advanced Clientless SSL VPN Configuration. In the IKEv2 IPsec Proposals panel, click Add. GRE tunnels are links between two points, with a separate tunnel for each link. All spokes connect directly to the hub using a tunnel interface. Can you please share output of following command on FW 1:packet-tracer input inside tcp10.0.1.1 47 10.0.2.1 47 detail, and the following command on FW 2:packet-tracer input inside tcp10.0.2.1 4710.0.1.1 47 detail, Phase: 1Type: ACCESS-LISTSubtype:Result: ALLOWConfig:Implicit RuleAdditional Information: Forward Flow based lookup yields rule: in id=0xd8ec9130, priority=1, domain=permit, deny=false hits=0, user_data=0x0, cs_id=0x0, l3_type=0x8 src mac=0000.0000.0000, mask=0000.0000.0000 dst mac=0000.0000.0000, mask=0100.0000.0000 input_ifc=inside, output_ifc=any, Phase: 2Type: ROUTE-LOOKUPSubtype: inputResult: ALLOWConfig:Additional Information:in 0.0.0.0 0.0.0.0 outside, Phase: 3Type: IP-OPTIONSSubtype:Result: ALLOWConfig:Additional Information: Forward Flow based lookup yields rule: in id=0xd8ecd028, priority=0, domain=inspect-ip-options, deny=true hits=0, user_data=0x0, cs_id=0x0, reverse, flags=0x0, protocol=0 src ip/id=0.0.0.0, mask=0.0.0.0, port=0 dst ip/id=0.0.0.0, mask=0.0.0.0, port=0, dscp=0x0 input_ifc=inside, output_ifc=any, Phase: 4Type: IP-OPTIONSSubtype:Result: ALLOWConfig:Additional Information: Reverse Flow based lookup yields rule: in id=0xd8e9d050, priority=0, domain=inspect-ip-options, deny=true hits=1, user_data=0x0, cs_id=0x0, reverse, flags=0x0, protocol=0 src ip/id=0.0.0.0, mask=0.0.0.0, port=0 dst ip/id=0.0.0.0, mask=0.0.0.0, port=0, dscp=0x0 input_ifc=outside, output_ifc=any, Phase: 5Type: FLOW-CREATIONSubtype:Result: ALLOWConfig:Additional Information:New flow created with id 1, packet dispatched to next moduleModule information for forward flow snp_fp_tracer_dropsnp_fp_inspect_ip_optionssnp_fp_tcp_normalizersnp_fp_translatesnp_fp_adjacencysnp_fp_fragmentsnp_ifc_stat, Module information for reverse flow snp_fp_tracer_dropsnp_fp_inspect_ip_optionssnp_fp_translatesnp_fp_tcp_normalizersnp_fp_adjacencysnp_fp_fragmentsnp_ifc_stat, Result:input-interface: insideinput-status: upinput-line-status: upoutput-interface: outsideoutput-status: upoutput-line-status: upAction: allow, Phase: 1Type: ROUTE-LOOKUPSubtype: inputResult: ALLOWConfig:Additional Information:in 0.0.0.0 0.0.0.0 outside, Phase: 2Type: ACCESS-LISTSubtype: logResult: ALLOWConfig:access-group fuck globalaccess-list fuck extended permit ip any anyAdditional Information: Forward Flow based lookup yields rule: in id=0xd8d7c820, priority=12, domain=permit, deny=false hits=2, user_data=0xd6c66a60, cs_id=0x0, use_real_addr, flags=0x0, protocol=0 src ip/id=0.0.0.0, mask=0.0.0.0, port=0 dst ip/id=0.0.0.0, mask=0.0.0.0, port=0, dscp=0x0 input_ifc=any, output_ifc=any, Phase: 3Type: IP-OPTIONSSubtype:Result: ALLOWConfig:Additional Information: Forward Flow based lookup yields rule: in id=0xd8d754e8, priority=0, domain=inspect-ip-options, deny=true hits=2, user_data=0x0, cs_id=0x0, reverse, flags=0x0, protocol=0 src ip/id=0.0.0.0, mask=0.0.0.0, port=0 dst ip/id=0.0.0.0, mask=0.0.0.0, port=0, dscp=0x0 input_ifc=inside, output_ifc=any, Phase: 4Type: NATSubtype:Result: ALLOWConfig:object network router-static nat (inside,outside) static 30.30.30.3Additional Information:Static translate 10.0.2.1/47 to 30.30.30.3/47 Forward Flow based lookup yields rule: in id=0xd8d7bd60, priority=6, domain=nat, deny=false hits=3, user_data=0xd8d7b710, cs_id=0x0, use_real_addr, flags=0x0, protocol=0 src ip/id=10.0.2.1, mask=255.255.255.255, port=0 dst ip/id=0.0.0.0, mask=0.0.0.0, port=0, dscp=0x0 input_ifc=inside, output_ifc=outside, Phase: 5Type: IP-OPTIONSSubtype:Result: ALLOWConfig:Additional Information: Reverse Flow based lookup yields rule: in id=0xd8d51710, priority=0, domain=inspect-ip-options, deny=true hits=2, user_data=0x0, cs_id=0x0, reverse, flags=0x0, protocol=0 src ip/id=0.0.0.0, mask=0.0.0.0, port=0 dst ip/id=0.0.0.0, mask=0.0.0.0, port=0, dscp=0x0 input_ifc=outside, output_ifc=any, Phase: 6Type: FLOW-CREATIONSubtype:Result: ALLOWConfig:Additional Information:New flow created with id 3, packet dispatched to next moduleModule information for forward flow snp_fp_tracer_dropsnp_fp_inspect_ip_optionssnp_fp_tcp_normalizersnp_fp_translatesnp_fp_adjacencysnp_fp_fragmentsnp_ifc_stat. Lastly, we define the Tunnel Destination IP address. or transport protocol, but in this case carry IPv6 as the passenger protocol with the GRE as the carrier protocol and IPv4 The hub router is configured with three separate tunnel interfaces, one for each spoke: Each GRE tunnel between the hub-spoke routers is configured with its unique network ID. For example, there is a feature, called Zone-based Firewall for Cisco routers. and sent to the peer, and the associated SA decrypts the ingress traffic to the VTI. i followed his video and try to configure the GRE tunneling on R1 and R3 however i managed to bring up the interface tunnel 0 up the interface but after i finish the ip address. Exceptions may be present in the documentation due to language that is hardcoded in the user interfaces of the product software, language used based on RFP documentation, or language that is used by a referenced third-party product. ASAs do not support the termination of GRE tunnels. tunnel If VPN tunnel is terminated on ASA and GRE tunnel is terminated on a router behind ASA, then the firewall rules which could be applied to the data traffic coming out of VPN on ASA are no more relevant. Attached are the topology and configurations. After it is done, we will proceed with the configuration. You are absolutely right, that looping traffic between Router and ASAs increases utilization of gears. I'm trying to connect VLANs from a network to VLANs of another network but it's not working. the exchange from subsequent decryption. The tunnel is up/up but there is no traffic going through it. an IPsec site-to-site VPN. source Can you tell me what's missing in my configurations ? New here? The second thought. After being decrypted, GRE traffic went back to Router. Multicast traffic is not supported. After being decapsulated from all VPN headers (IPsec and GRE), the traffic can be controlled and inspected as you like. 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