Gre tunnel line protocol down

– In the verification section below, note the proxy identities in the IPsec SA. 1 YES manual up down. It isn't a port. I can't get OSPF to work over a GRE tunnel. The ACL can be much narrower in a secure GRE tunnel, because you again have two peering interfaces. The only thing that changed in the get vpn 2nd output was on the last line: U 10. When you enable tunnel keepalives, the tunnel is considered “down” when the keepalives fail repeatedly. As the name implies, it is a mechanism or tunneling protocol that permits the encapsulation of many different IP protocols inside an arbitrary transport protocol. GRE Tunnel Recursive Routing line protocol is up Hardware is Tunnel Internet The introduction of a routing protocol across a GRE tunnel can cause an CCNA Security - GRE Tunnel (include HSRP also) ip forward-protocol nd ! line con 0 exec-timeout 0 0 privilege level 15 logging synchronous line aux 0 exec The red line indicates a GRE tunnel. Question 3. At this point I have removed any ACLs. 0. 1. Y. 255 Source Y. 13/30 MTU 1514 bytes, BW 10000 Kbit, DLY 500000 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation TUNNEL, loopback not set Keepalive set (10 sec), retries 3 Tunnel source 10. 129 local 172. I never knew you could do GRE on a linux box :) Anyway, I am guessing you're seeing the line protocol down due to the keepalive command. 223. The GRE-HEADEND router has a static route that is shorter prefix to reach the tunnel destination address of the remote routers – ip route 172. Hi, Make sure GRE is set to multipoint on the Tunnel if you have more than on interface connecting to the Hub, such as a Checking Whether the Protocol Status of the Tunnel Interface Is Normal Procedure Run the display this interface or display ip interface brief command on the tunnel interface to check whether the interface status is normal. By default, a GRE tunnel is protocol up, if the physical interface is up/up and there is a route to the GRE destination; If the far side of the GRE tunnel is not configured or down, this will cause a black-hole for traffic; In order to ensure end-to-end reachability, keepalives are used (off by default) Configuration Hi guys, I'm trying to get this section work, and I thought of configuring a gre tunnel between Sw2 and R5, as it does not break the statements. d . 1/31, MTU 1476 bytes, encapsulation GRE Keepalive is not Enabled Path MTU Discovery: Enabled, MTU is 1428 bytes, age-timer: 10 minutes Path MTU will expire in 0 minutes 50 secs Tunnel4 is up, line protocol is down Hardware is Tunnel Description: Internet address is 10. Re: Qos cannot get it to work with ipsec over gre tunnel matt Sep 24, 2013 12:34 PM ( in response to touristsis ) You made this post for a NetVanta 7000 series, but it looks like this is for a different product. 10 Tunnel mode gre ip Port name is GRE_10_to_VR1_on_FCX_STACK Internet address is 223. After it is done, we will proceed with the configuration. 7 Testing a GRE Tunnel. They forward Internet traffic to the WAN gateway port, fa4, which uses the GRE tunnel interfaces tunnel 2700 and tunnel 2800 to send the Internet traffic through the GRE tunnel to the Zscaler service. X. Reset/down – This is usually a transient state when the tunnel is reset by software. 4. We have a 6 spoke DMVPN setup. GRE encapsulation supports any OSI Layer 3 protocol. Line protocol current state : DOWN Description: Route Port,The Maximum Transmit Unit is 1500 Internet Address is 5. 10 Tunnel destination is 1. Question 5. 2. Question 5 اگر به هر دلیلی پاسخ برنگردد به معنی down بودن طرف مقابل ارتباط تونل GRE است. Interface IP-Address OK? Method Status Protocol GigabitEthernet0/0 192. 1 Lab 7 The adaptation of the GRE Tunnel Bonding protocol to the multi-provider scenario is left as future work. The tutorial shows configuration of OSPF routing protocol, GRE and IPSec tunnel on Cisco 7206 VXR router and appliance running VyOS network OS. Serial1/0 is administratively down, line protocol is down, encapsulation is HDLC DECnet protocol processing not enabled Serial1/1 is administratively down, line protocol is down, encapsulation is HDLC DECnet protocol processing not enabled Serial1/2 is administratively down, line protocol is down, encapsulation is HDLC View Configure, Verify, and Troubleshoot GRE Tunnel Connectivity. Note: The line protocol on a GRE tunnel interface is up as long as there is a router to the tunnel destination. I simulated this in gns3, the moment you add ‘tunnel mode ipv6’ on the tun34 int on R4, its line protocol goes down. Not sure on the linux config for keepalives, but it looks like there's nothing to configure keepalives on the linux side. 3. But what if we are using GRE. 1/31, MTU 1476 bytes, encapsulation GRE Keepalive is not Enabled Path MTU Discovery: Enabled, MTU is 1428 bytes Tunnel0 is up, line protocol is up (connected) Hardware is Tunnel Internet address is 192. 2 255. We use the IP addresses on the GRE tunnel so we can establish an OSPF adjacency between the two routers, the loopbacks are advertised in OSPF and learned through the GRE tunnel. 10. HTH. Phase 2 of Internet Protocol Security (IPSec) is established, but BGP isn’t established. If 3 in a row are missed, the tunnel’s line protocol is brought down. x. In this case i had to include the public addresses in the network command. B. When we do a show interface it shows the Tunnel 0 is up, but the protocol is down. That means the link is good and the interface is functioning normally. The problem is, that while line protocol of Tu0 in ME-C3750-24TE is up, it is down in C1841: ME-C3750-24TE#sh int Tu0 Tunnel0 is up, line protocol is up Hardware is Tunnel Interface is unnumbered. 2 (Serial0/0/0), destination 64. 41. GRE tunnels are IP-over-IP tunnels which can encapsulate IPv4/IPv6 and unicast/multicast traffic. GRE tunnel provides a way to encapsulate any network layer protocol over any other network layer protocol. 50. Sending 2, 100-byte ICMP Echos to 3::3, timeout is 2 seconds: Packet sent with a source address of 2::2!! Success rate is 100 percent (2/2), round-trip min/avg/max = 16/38/60 ms R2# A Generic Routing Encapsulation (GRE) tunnel is a non-secure, site-to-site VPN tunneling solution that is capable of encapsulating any Layer 3 protocol between multiple sites across over an IP internetwork. The GRE Tunnel Bonding Protocol is developed by Huawei and has been deployed in networks operated by Deutsche Telekom AG. show ip interface brief | include Tunnel – This command can be used to determine is up or down. GRE is a Cisco developed protocol which is one of many tunneling protocols. Have a GRE Tunnel from a router heading to a switch through an IPSEC tunnel setup by the router to an ASA. Use the Cisco IOS command line interface (CLI) to access your router’s global configuration command mode. Then you configure IP address of the tunnel – Overlay network. From the output, we see the the line “Serial0/1 is up, line protocol is up”. In addition to the BGP routing protocol, Open Shortest Path First (OSPF) is enabled on all company routers. 0 WAN Technologies March 17, 2018 April 2, 2018 1 Minute To configure a GRE tunnel (modify accordingly): device # show interface tunnel 10 Tunnel10 is up, line protocol is up Hardware is Tunnel Tunnel source 1. For this reason GRE tunnel is very often used in conjunction with IPSec. There is basic BGP configured to the MPLS Backbone on all 4 routers and they are receiving a default route via that Provider. Note: If due to a keepalive drop the tunnel goes to up/down state, enable debug tunnel and debug tunnel keepalive . If the protocol status is down, go to Checking Whether the Physical Interface Status Is Normal. Typically, GRE tunnel is encapsulated inside the IPSec tunnel and this model is called GRE over IPSec. After connecting to other Router: Router#sh ip int brief Line Protocol Down Locally on the Router. The GRE tunnel is created first, then ipsec is used to encrypt the content of the tunnel. Description: Tunnel Interface. 18. The tunnel does not come up unless traffic is sent through Generic Routing Encapsulation (GRE) is one of the available tunneling mechanisms which uses IP as the transport protocol and can be used for carrying many different passenger protocols. It is inside GRE header (Overlay) which is a payload for Underlay network where public addressing is used. 255 Ethernet0 As a side note, is this (GRE tunnel through the PIX) a good design from the security point of view? View Configure, Verify, and Troubleshoot GRE Tunnel Connectivity. R1#configure terminal Enter configuration commands, one per line. Cisco CCNA GRE. There are four possible states in which a GRE tunnel interface can be: 1. 19 The GRE packet sent by that tunnel is being routed again through that same tunnel. Rick If we are using tunnel mode it is basically a tunneling mechanism that hides everything inside a header trailer capsule. 255. 38 Re: Help with GRE tunnel in comware7 I have be trying to get GRE tunnel UP on comware 7 - 5900 model. 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 segment size to 1360. Then you need to specify the source and destination of the GRE tunnel. 1 (Ethernet0/0/1), destination 2. 0 s0/0. After the GRE tunnel is set up, the routing protocol can be implemented. This isn't the problem though, on the HP MSR it has a WAN link which the other side of the interface is tagged for the VPN-instance. The tunnel is working perfectly if I configure static routes. + The interface that anchors the tunnel source is down. Au moment ou le tunnel GRE a été établi et semblait fonctionner, les interfaces tunnel 0 sur les deux routeurs n'arrétaient pas de virer up et down alternativement et foutait tout en l'air message d'erreur de type: The controller determines the status of a GRE tunnel by sending periodic keepalive frames on the Layer-2 or Layer-3 GRE tunnel. When the tunnel drops, the GRE tunnel on the Cisco side drops first, then the IPSec tunnel drops. GRE Configuration Example: Cisco 881 ISR. Tunnel 199 is up line protocol is up. 164. Other spokes and the hubs can ping it's ip, but it can't ping itself. The tunneling protocol works by using the data port . It functions as a tunneling protocol covering a mixture of network layer protocols inside IP tunnels and is stateless with no relation between successive request-response pairs. 30. BGP over GRE Tunnel. Part of the magic of GRE is that the other end does not need any special configuration to listen and respond to the keepalives. Just a followup: the reason that GRE tunnels almost always show "up/up" is that the state of the tunnel's line protocol is controlled by the presence or absence of a *route* to the tunnel destination. If the tunnel is in the below state then the tunnel has formed correctly: “Tunnel100 is up, line protocol is up” You have successfully protected your GRE tunnels with IPsec. 1 Lab 7 i am doing this topology lab and configure gre tunnel over router R2 and R1 to connect area 2 my problem is when i enable ospf on it links come up and then down recursive lookup massage come. Loopback0 unassigned YES unset up up. Question 4. I am trying to configure a GRE tunnel between a CE6850 & a Cisco Catalyst 6509 switch. Re: GRE Tunnel Line Protocol Down 1) Check your routes, there has to be a valid route in the routing table for the tunnel to know where the destination is 2) Double check you are allowing protocol 47 to pass from the "outside" to the "inside" GRE Tunnel is down. GRE Tunnel Recursive Routing. In case you still need help, Please post you're configuration ( preferably from both the Fortigate and the ASA ) you may send it via mail for more security. Question 6 If not, troubleshoot before continuing to the next part. 10 Tunnel mode gre ip Port name is GRE_10_to_VR1_on_ICX_STACK Internet address is 223. device # show interface tunnel 10 Tunnel10 is up, line protocol is up Hardware is Tunnel Tunnel source 1. Cisco Bug: CSCvc78926 - GRE tunnel is up but line protocol is down with GRE tunnel keepalive configuration on CRS Topaz I am trying to establish a GRE/IP tunnel over the Internet: interface Tunnel1 description GRE-Tunnel ip unnumbered GigabitEthernet7/0/0 no ip directed-broadcast tunnel source Loopback1 tunnel destination x. set protocol 47 // restrict traffic selectors to GRE protocol (ip/47) set auto-negotiate enable set encapsulation transport-mode // transport-mode for IPsec (tunneling already done by GRE) next end # # Local and remote overlay IP addresses over the GRE-IPsec tunnel # config system interface edit "toCisco" Knowing where to apply the crypto map is essential because this can get a little tricky while configuring IPsec over GRE. GRE creates a virtual point-to-point link to Cisco routers at remote points, over an IP internetwork. 22. Generic Routing Encapsulation (GRE) is a protocol for encapsulation of an arbitrary network layer protocol over another arbitrary network layer protocol. 100 “Under normal circumstances, there are only three reasons for a GRE tunnel to be in the up/down state: + There is no route, which includes the default route, to the tunnel destination address. DMVPN Tunnel 0 Up - Line Protocol Down. On the 6th spoke, a 2911, we have created a Tunnel0. A small detail regarding the route you made, Is it pointing to the GRE interface itself or the remote IP of the tunnel ? I would use the remote IP just to be sure. Source 10. To create a GRE tunnel on Linux, you need ip_gre kernel module, which is GRE over IPv4 tunneling driver. Then it was noticed that is a site went down even briefly and the tunnel dropped, the tunnel would never re-establish itself (The tunnel interface remained line up/protocol down). 2 service timestamps debug uptime service timestamps log uptime service password-encryption ! hostname r2 ! logging buffered 4096 debugging ! username all memory-size iomem 10 ip subnet-zero ! ! ip domain name hellocomputers. Thus, if a) the IP address of the tunnel destination is on the Internet, GRE stands for Generic Routing Encapsulation. 2 : The private Lan on R4 are being advertised by the public ip interface of the R4 instead of Re: GRE tunnel line protocol down on one side only That must mean that Site #2 has no valid route to the IP address of the interface hosting the tunnel at site #1. 24. Question 2. On the reception of a keepalive response, with the implication that the tunnel endpoint is again reachable, the tunnel keepalive counter is reset to 0 and the line protocol on the tunnel comes up. The router that first recognizes this routing loop problem would shut down the tunnel immediately. Judging by your configuration your ADSL modems probably login for you, which means that your WAN IP will exist on the ADSL modem, and not the Cisco router, which means you cant establish a tunnel from the Ciscos. Generic routing encapsulation (GRE) is a tunneling protocol which was initially developed by Cisco, and later it has been adopted as an industry standard in RFC 2784. Approaches specified in this document might as well be used by other tunneling technologies to achieve Current configuration : 2557 bytes ! version 12. com ip name-server 4. X 255. REMOTE CONSOLE LOG A GRE Tunnel Established on an NE40E Is Displayed as Down on One Side and Up on the Other Side Information No relevant resource is found in the selected language. ENSP做IPsec over GRE 后Line protocol current state : DOWN 的问题 tunnel-protocol gre interface Tunnel 0/0/1 进入 GRE Essentially, a tunnel a a 3945 will go down/down although the tunnel on the remote router indicates it is up/up. tunnel vlan 33 . Sign In Register Home › Cisco CCIE › CCIE Routing & Switching › CCIE RSv5 Workbooks › CCIE Routing & Switching Lab Workbook Volume III Version 4. Add a static route like this to r1's configuration: ip route 150. This post doesn't show other solution than Solved: Enviroment: Multiple ER Lites at distributed sites with dynamically assigned addresses on broadband OSPF over GRE/IPSEC from each ER Lite to GRE over IPSEC UP but not working hi, I'm trying an easy setup in my lab where I've FGT1---FGT_ISP---FGT4 connedted. Hi guys, I'm trying to get this section work, and I thought of configuring a gre tunnel between Sw2 and R5, as it does not break the statements. c. r1 (bb2) learns the route to the destination of the GRE tunnel, 150. 5. Otherwise the line protocol will go down. The tunnel communicates fine, it sees an EIGRP neighbor on both sides and the routes are sent across just fine however the tunnel is in a state of constant bouncing. While it is a Cisco developed protocol, it is also defined in several RFCs (1701, 1702 and 2784). This document makes this protocol available to the public, thereby enabling other developers to build interoperable implementations. A GRE Tunnel Established on an NE40E Is Displayed as Down on One Side and Up on the Other Side Information No relevant resource is found in the selected language. Once have a GRE tunnel set up between two endpoints, and an interface for mirrored traffic to ensure that no mirrored traffic is routed on the linux (virtual) machine, an unused GRE Ethernet tunnel can be tested by running ping on one end and tcpdump on the other to see the GRE tunnel traffic. Both sides can ping the respective tunnel configured destinations however on the 5510 side, the line protocol is down. 2, via that same GRE tunnel. DSL: Digital Subscriber Line. This means that each tunnel end-point does not keep any information about the state or availability of the remote tunnel end-point. Otherwise, the tunnel just stays up (if the tunnel source is up). Up/down – This implies that, even though the tunnel is administratively up, something causes the line protocol on the interface to be down. RE: GRE Tunnel: Line Protocol Down? BuckWeet (IS/IT--Management) 14 Nov 08 21:40 Its because when you bring up the tunnel the static routes that you have for the tunnel interfaces kick in. 103. GRE does not include strong security to protect its payload. - Create a GRE tunnel between R4 and R5 using the addresses 10. This can be seen by display interface tunnel [10500]display interface tunnel 1 Tunnel1 Current state: DOWN Line protocol state: DOWN Notice the bolded lines in the second tunnel output. 42. A GRE tunnel is used when packets need to be sent from one network to another over the Internet or an insecure network. The GRE tunnel can show "tunnel down and line protocol up" in the following scenarios: Cannot find destination route or route points to Management Interface; Configured Keepalive is down; If the source IP is loopback/VE and if IP interface is disabled; Source IP is physical port and physical port is not up TUNNEL LINE PROTOCOL DOWN 1: The public ip addresses shouldnt be participating in the routing process before the tunnel comes up. 7. GRE Tunnel down. Follow @ASM_Educational Cisco CCNA GRE Tunnel Configuration Now I will do small Lab:The Goal is that PC1 (private Network) be able to Ping PC2 another Private Network, by going Via R3 which represent internet. If the tunnel status is UP, verify that the Details column has one or more BGP routes listed. Re: Monitor status of VPN tunnel on Cisco router. 168. [HELP] Gre Tunnel Protocol Down. Why is protocol keep saying its down? R1-SW# show. The EIGRP route is then lost, and the RIPv2 route returns; the tunnel is then being brought up again; the cycle continues indefinitely until a configuration change is made. 14. became. When I change vlans the capture stops. GRE is an Internet Engineering Task Force (IETF) standard defined in RFC 2784. This document bases the solution on GRE (Generic Routing Encapsulation ) since GRE is widely supported in both fixed and mobile networks. as someone suggested earlier, in the networktut lab, R3 doesn’t have an ipv6 add although R4 does, so transport has to be ipv4-GRE. GRE Tunnel configuration In order to configure GRE tunnel interface, you need to specify source IP address (or interface) and destination IP address of the tunnel – Underlay network. Y Destination X. If the protocol status is up, go to Checking the Route to the Destination Address of the Tunnel Interface. The encrypted traffic is for the tunnel source and tunnel destination IPs with protocol number 47, which is the assigned protocol number for GRE. Generic Routing Encapsulation (GRE) is a method to tunnel IP packets between two end points. The tunnels behave as virtual point-to-point links that have two endpoints identified by the tunnel source and tunnel destination addresses at each endpoint. 19. I've an ipsec running b/w FGT1 and FGT4 that is up and traffic goes through. Tunnel mtu is set to 1200. So first make sure that ip_gre is loaded. L2TP VPNs need TCP and UDP port 1701 and GRE protocol access to port 47. 94. It happens intermittently and I am not seeing anything in the logs, other than the tunnel goes down. Thanks, Lee Method Status Protocol GigabitEthernet1 172. Running head: CONFIGURE, VERIFY, AND TROUBLESHOOT GRE TUNNEL CONNECTIVITY 1 Configure, Generic Routing Encapsulation (GRE) is one of the available tunneling mechanisms which uses IP as the transport protocol and can be used for carrying many different passenger protocols. i have apply this configuration on my router and all the interface is up only the two tunnel interface the status is up but the protocol is down, any help? my question is how can make the protocol of tunnel 1 and 2 up, by the way when i make reload for the router the protocols of tunnels comes up for 10 sec after that again change to down GRE Tunnel up down. As Ethernet technology has evolved (higher speeds, different media, switch connections, etc) the mechanics of the protocol have evolved but the purpose is still to determine the operational state of the interface. b. keep alive 5 4 - where 5 in this case is the frequency and 4 is the retry before considerd down LAB 1 General Gre tunnel line protocol is up Hardware is Tunnel This way we can create a GRE tunnel between the two routers, otherwise they don’t know how to reach each others IP address. net tunnel. The difference is the gre tunnel packet header. 7 YES DHCP up up Tunnel99 10. 211. submitted 2 years ago * by OUScotty. R1 can communicate with the ISP address of REMOTE-ROUTER without any trouble, however the GRE Tunnel1 interface is flapping up and down. EIGRP is running over the GRE tunnel itself. ipv6 route 2::/64 tunnel 0! R3#sh ip int tun0 Tunnel0 is up, line protocol is down Internet protocol processing disabled R3# R2# ping 3::3 repeat 2 source 2::2 Type escape sequence to abort. Since this is a shorter prefix, the GRE-HEADEND router will eventually learn a better route via EIGRP and will try to use that to reach The tunnel communicates fine, it sees an EIGRP neighbor on both sides and the routes are sent across just fine however the tunnel is in a state of constant bouncing. Running head: CONFIGURE, VERIFY, AND TROUBLESHOOT GRE TUNNEL CONNECTIVITY 1 Configure, The tunnel interface allows for peering, which is required for most dynamic routing protocols. Then I've a gre-tunnel over the IPSEC and an ip address setup over the gre-tunnel itself. x end Pretty much no matter what I do the interface status is always: Tunnel1 is up, line protocol is down device # show interface tunnel 10 Tunnel10 is up, line protocol is up Hardware is Tunnel Tunnel source 1. Also the encapsulation used on this interface is HDLC -> The other end must use the same encapsulation. Overview GRE tunnels are designed to be completely stateless. Creating a GRE tunnel only takes a couple of commands, and really is not much different than creating any non-physical interface: R7#conf t Enter configuration commands, one per line. Acronyms and Terminology GRE: Generic Routing Encapsulation . It involves allowing private network communications to be sent across a public network (such as the Internet) through a process called encapsulation. 2. I deleted the configuration lines for 2nd and readded them and, after that, second GRE tunnel came back up. A consequence of this is that the local tunnel end-point router does not have the ability to bring the line protocol of the GRE tunnel interface down if the remote end-point is unreachable. Issue with this tunnel is that whenever WAN connection goes down Line protocol on tunnel interface some times comes up and sometimes not (therefore we have to reset the tunnel interface and it comes up). With no capture filter the GRE vlan packets have the tunnel scr and dst IP's in the first IP header and the gre part of the header has the IP that I'm trying to capture. 242. GRE encapsulates the original IP packet with a new IP header also appending an additional GRE header. 1 › IEWB-RS Volume 3 Version 4. 1/31, MTU 1476 bytes, encapsulation GRE Keepalive is not Enabled Path MTU Discovery: Enabled, MTU is 1428 bytes, age-timer: 10 minutes Path MTU will expire in 0 minutes 50 secs Generic Routing Encapsulation (GRE) is one example of a basic, non-secure, site-to-site VPN tunneling protocol. 1 ! ip audit notify log ip audit po max-events The tunnel used so far in all of the examples in this recipe hasn't specified any particular tunnel protocol, so the routers will use the default GRE protocol. A GRE tunnel is used when packets need to be sent from one network to another over an unsecure network. PPTP VPNs need TCP and UDP port 1723 open and IP port 47 must pass the General Routing Encapsulation (GRE) protocol. so pls tell me what is recursive lookup and and what is the reason for recursive lookup. At site #2, look at the config of Tunnel10, look for the tunnel destination a. However the tunnel will not come up on the 6850, although i have layer 3 connectivity between the source & destination ip address's. In computer networks, a tunneling protocol is a communications protocol that allows for the movement of data from one network to another. GRE allows the encapsulation of a wide variety of network layer protocols inside virtual point-to-point links. For example, you can also transport multicast traffic and IPv6 through a GRE tunnel. GRE is a protocol that runs over IP. Destination 10. 6 (GigabitEthernet0/0), destination 10. 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. From the Cisco side, here is the exact order of events per the log: *Tunnel 495 is the IPsec tunnel, Tunnel 496 is the GRE tunnel Generic Routing Encapsulation (GRE) is a tunneling protocol developed by Cisco Systems that can encapsulate a wide variety of network layer protocol packet types inside IP tunnels, creating a virtual point-to-point link to Cisco routers at remote points over an Internet Protocol (IP) internetwork. If you do things right, you will be able to send traffic through the tunnel. R 10. Thus, if a) the IP address of the tunnel destination is on the Internet, General Routing Encapsulation (GRE) for Packet Encapsulation For companies with VPNs, this protocol is applicable as it encloses IP packets for tunneling the traffic. I have a GRE tunnel that is running between a Comware 5510HI and MSR954. Tried with service-loopback binded to physical interface but still tunnel is showing down down. Administratively down/down – This implies that the interface has been administratively shut down. SYMPTOM: GRE tunnel Interface is Down if it is Configured in a VPN Instance SYMPTOM: The GRE tunnel is down. At this point, the second GRE tunnel had line protocol down. If the Interface State Control feature is enabled for Dynamic Multipoint VPN (DMVPN) and none of the NHSs respond, then the line protocol is put in a down state. Hi, Make sure GRE is set to multipoint on the Tunnel if you have more than on interface connecting to the Hub, such as a 4. A consequence of this is that the local tunnel end-point router does not have the ability to bring the line protocol of the GRE Tunnel interface down if the remote end of the tunnel is unreachable. In such a case, a network administrator can manually bring the interface down in order to remove any routes (specifically static routes ) in the routing table that use that interface as the outbound interface. docx from CIT 276 at University of Phoenix. It involves allowing private network communications to be sent across a public network through a process called encapsulation. The tunnel source should be your external WAN IP, and the destination should be the WAN IP of the other end. Because tunneling involves repackaging the traffic data into a different form, perhaps with encryption as standard, it can hide the nature of the traffic that is run through a tunnel. 122. 97. The tunnel between R1 and R3 is currently running GRE, the default encapsulation: R1# show int tun0 | include protocol Tunnel0 is up, line protocol is up Tunnel protocol/transport GRE/IP A ping from one end of the tunnel's 10. Inter Tunnel Flooding is enabled. The tunnel interface allows for peering, which is required for most dynamic routing protocols. اگر به هر دلیلی پاسخ برنگردد به معنی down بودن طرف مقابل ارتباط تونل GRE است. Loopback1. GRE tunneling is accomplished by creating routable tunnel endpoints that operate on top of existing physical and/or other logical endpoints. IKE Configuration The GRE General Test. 255 Ethernet0 As a side note, is this (GRE tunnel through the PIX) a good design from the security point of view? Generic Routing Encapsulation (GRE) GRE Tunneling to Provide Traditional Point-to-Point Functionality over Non-Traditional Network Infrastructures This configuration guide explains the concepts behind configuring your Secure Router Operating System (SROS) product to use GRE tunneling, defines related commands, and provides sample configurations. 2 ! If the protocol status is up, go to Checking the Route to the Destination Address of the Tunnel Interface. The keepalive is double-encapsulated, so the remote peer receives the keepalive, decapsulates it, and is ‘tricked’ into sending the response back to the original source. Tunnel 1 is up line protocol is down Description: Tunnel Interface Internet address is X. 165. 1 Tunnel protocol/transport GRE/IP, key disabled keepalive disabled Checksumming of packets disabled Re: Help with GRE tunnel in comware7 I have be trying to get GRE tunnel UP on comware 7 - 5900 model. I also have other GRE tunnels going from the same HP5510 to different MSR's which are working fine, config is replicated, so this is odd. 1/31, MTU 1476 bytes, encapsulation GRE Keepalive is not Enabled Path MTU Discovery: Enabled, MTU is 1428 bytes, age-timer: 10 minutes Path MTU will expire in 0 minutes 50 secs B An IPsecGRE tunnel must use IPsec tunnel mode C GRE encapsulation occurs from IT 205 101 at University of Phoenix 2. 163. Only that one of those tunnels will encrypt and other will not. Review the Status of your VPN tunnel. d , then do a show ip route a. Generic Routing Encapsulation (GRE) GRE Tunneling to Provide Traditional Point-to-Point Functionality over Non-Traditional Network Infrastructures This configuration guide explains the concepts behind configuring your Secure Router Operating System (SROS) product to use GRE tunneling, defines related commands, and provides sample configurations. پس چنانچه در چند بازه زمانی، فرستنده مکانیزم keep-alive پاسخ را دریافت نکند، line protocol اینترفیس Tunnel خود را down می نماید. 0/30 subnet to the other verifies end-to-end connectivity. 235. Key point here is the packets that are travelling in a GRE tunnel are not encrypted as GRE does not encrypt the tunnel but You are troubleshooting an issue with a GRE tunnel between R1 and R2 and find that routing is OK on all intermediary routers. 38 0x00000002 2nd. 0 255. 1/24 dev gre0 GRE Tunnel Recursive Routing. Part 3: Enable Routing over the GRE Tunnel In Part 3, you will configure OSPF routing so that the LANs on the WEST and EAST routers can communicate using the GRE tunnel. This way we can create a GRE tunnel between the two routers, otherwise they don’t know how to reach each others IP address. However if the tunnel is in the below state then you may need to look back over IPsec configuration: “Tunnel100 is up, line protocol is down” We are using this tunnel from a branch office to Hub office. 160. GRE is a tunneling protocol developed by Cisco that can encapsulate a wide variety of protocol packet types inside IP tunnels. It is both administratively up and it’s protocol is up as well. 11 ttl 255 sudo ip link set gre0 up ip addr add 10. Tunnel is a Layer2 GRE TUNNEL. This usually happens when the tunnel is misconfigured with a Next Hop Server (NHS) Re: GRE Tunnel - Line Protocol: Down Thanks for your reply. 1/30 ! Can't have the same IP on the GRE tunnel on both ends MTU 17916 bytes, BW 100 Kbit/sec, DLY 50000 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation TUNNEL, loopback not set Keepalive not set Tunnel source 209. We recreated the problem in our lab and it consistently failed. X Tunnel mtu is set to 1100 Tunnel is an IP GRE TUNNEL Tunnel is Trusted Inter Tunnel Flooding is enabled Tunnel keepalive is enabled Tunnel keepalive interval is 10 seconds, Multipoint GRE (mGRE) Tunnel Interfaces. Now I've spent hours and hours trying to figure GRE out, this was not included in my CCNP ROUTE material except for some DMVPN using mGRE, however I did want to know for practical purposes how to encapsulate broadcast / multicast traffic over an IPSec tunnel which in turn needs a GRE tunnel as there… r1 (bb2) learns the route to the destination of the GRE tunnel, 150. One of the "unknown" addresses is the remote's public IP address which you use for the tunnel destination. 2 YES manual up down In the EC2 instance , I got the following configuration modprobe ip_gre lsmod | grep gr sudo ip tunnel add gre0 mode gre remote 35. This is a big benefit. Up/up – This implies that the tunnel is fully functional and passes traffic. If the tunnel status is DOWN but the Details column is IPSEC IS UP, be sure to configure BGP properly on your firewall. Which two possible issues can prevent the tunnel from coming up? (Choose Two) A. The router performs NAT on the other traffic that it sends directly to the Internet. Interesting. Cisco WAN :: 2911 - DMVPN Tunnel 0 Up - Line Protocol Down Jul 8, 2011. GRE tunneling GRE is a tunneling protocol that was originally developed by Cisco, and it can do a few more things than IP-in-IP tunneling. All other tunnels terminated on Hub router are working fine. BGP over GRE Tunnel May 5, 2017 In this blog post we are going to explain how Generic Routing Encapsulation (GRE) tunnel might be used in a situation when the Border Gateway Protocol (BGP) speaking routers are connected via the non BGP-speaking routers. 3 Configure, verify, and troubleshoot GRE tunnel connectivity clinetworking 4. ENSP做IPsec over GRE 后Line protocol current state : DOWN 的问题 tunnel-protocol gre interface Tunnel 0/0/1 进入 GRE From the output, we see the the line “Serial0/1 is up, line protocol is up”. It's not just an EIGRP down or holding expired state, the line protocol on the tunnel goes down. - Configure the backup interface feature on R5 such that if the tunnel between R4 and R5 goes down the point-to-point Serial link between them is activated. 190. show interface Tunnel 0 – You can also verify the state of this interface with this command. 1/24 Encapsulation is TUNNEL, loopback not set Tunnel source 1. Normally, when you're connecting over an ISP, you just let the default route handle everything unknown. . Tunnel is Trusted. Y/24 that is sourced from and destined to the Frame Relay connection between them, and enable GRE keepalives. Five of the six spokes work fine. GRE is typically used between two Cisco devices to secure a tunnel over the Internet. GRE allows routers to act as if they have a virtual point-to-point connection to each other. 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. The tunnel is up on R1, but down on R2. Re: tunnel up line protocol down « Reply #8 on: September 22, 2011, 12:04:36 PM » Yeah not all IOS image feature sets support the 6in4 tunneling needed to use a HE. Tunnel keepalive is disabled. We moved the tunnel to an IOS router and that wasn’t affected. With GRE, a virtual tunnel is created between the two endpoints and packets are sent through the GRE tunnel. The controller determines the status of a GRE tunnel by sending periodic keepalive frames on the Layer-2 or Layer-3 GRE tunnel. YES manual up down. In the most general case, a system has a packet, that needs to be encapsulated and delivered to some destination, which is called payload. Not more than 10 seconds later everything comes back up. Featuring question types that closely reflect the kind of thinking you'll do in today's demanding graduate-level programs, the GRE ® General Test lets you show schools you are ready to succeed. For details on the Interface State Control Feature, see the DMVPN Tunnel Health Monitoring and Recovery Configuration Guide. If you prefer to use a different tunnel protocol, change it using the tunnel mode command as follows: Router1(config)#interface Tunnel1 Router1(config-if)#tunnel mode ipip If keepalives failed (the interface was disconnected from the media, the media was broken, etc) then the line protocol went down. i am doing this topology lab and configure gre tunnel over router R2 and R1 to connect area 2 my problem is when i enable ospf on it links come up and then down recursive lookup massage come. The router CE1 is connected to the router PE_ISP1 (ASN 64501) and the router CE2 is connected to the router PE_ISP2 (ASN 64502). If we are using GRE and then tunnel mode IPsec we will basically make tunneling and another tunneling inside the tunnel right. Generic Routing Encapsulation (GRE) is a tunneling protocol developed by Cisco Systems that can encapsulate a wide variety of network layer protocols inside virtual point-to-point links over an Internet Protocol internetwork. gre tunnel line protocol down

dj, ng, as, 4a, 4u, zo, yl, ip, li, uz, 4g, tp, 5j, qr, ns, pa, il, d6, iz, fr, oe, mf, 6g, wl, xo, 2k, 2g, qb, 1a, rg, jb,