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Network 10.1.24.2 0.0.0.0 area 0 There seems to be no problem in this environment, but the route summary has problems in the point-to-point LSP environment, such as MPLS VPN , TE. C 1.1.1.0 is directly connected, Loopback0 The downstream label was not transmitted, because LDP Neighbor was not established. 10.1.12.2 The unreservable bandwidth is the bandwidth remaining after being supplied to the TE , that is, the maximum bandwidth of the link minus the bandwidth currently reserved by the TE tunnel. System ID 6 -byte system ID , ES or IS identifier, similar to OSPF 's Router ID , each device has a system ID , and the IP network, each interface has an IP , which is the difference between one of . Note: The SystemID must be unique across the entire Area and trunk ( Level2 ). BGP routing problem, well, now we use the loopback interface on R1 and R4 to establish IBGP adjacency, the problem is solved. At this time R4 , the go 5.5.5.5 next hop of the R1 of Loopback port addresses, R4 at destined to 5.5.5.5 of the IP when the pressure package label, use is 1.1.1.1/32 routing tag, The same is true for R3 and R2 , then the label package can be opened through 1.1.1.1/32 . Time since created: 5 hours, 38 minutes Bw[5]: IS-IS hierarchy Outgoing interface The static route forwarding mode of the MPLS TE tunnel supports route recursion. 3 area addresses. The latest IOS version can be set to 255. If the maximum number of area addresses supported by the two routers is inconsistent, that is, the MAX.Areas field does not match, the IIH message is ignored . *Aug 18 04:37:06.243: min unit = 0 bytes,max pkt size = 1500 bytes R1#show ip route Type 9 flooding range only on this link PLR ( Point of local repair ): Local repair point, this is the head end of the backup tunnel TE tunnel is one-way / / Whether the local will retain all the label mapping messages received from the neighbor in the database Interface eth 0/0 Local binding: tag: 102 Peer-to-peer network lab environment Label DC 3.3.3.0 [115/20] via 10.1.123.3, FastEthernet0/0 10.0.0.0/24 is subnetted, 3 subnets Fa0/0 We have found, R6 originating packet is IP , to the R4 , R4 check CEF table, the destination found: 5.5.5.5 entry is associated with a the Label : 303 , then R4 will IP over cladding pressure tab 303 , and then lost Give the next hop 10.1.34.3 which is R3 . The following is the CEF entry for R4 : Tu0:403 We went to traceroute on R1 6.6.6.6 R1#traceroute 6.6.6.6 Ip address 10.1.12.1 255.255.255.0 R1#show mpls forwarding-table 0x2D6E Dynamic Hostname Exchange Mechanism for IS-IS R4#sh isis da I have already said it above. Frame-relay map ip 10.1.123.1 201 broadcast i L1 2.2.2.0 [115/10] via 10.1.123.2, FastEthernet0/0 10.0.0.0/24 is subnetted, 2 subnets Fa0/0 R5 configuration is as follows There is DIS in the LAN , DIS generates and updates the pseudo node information, and spreads the LSP in the LAN . The DIS sends CSNP every 10s , which lists the LSPs stored in its link state database . These CSNPs are multicasted to all IS-IS routers on the LAN . The configuration of R2 is as follows (all configurations are omitted from the configuration of interface IP ): Ip router isis Continue to show it: Reservable Bandwidth[1]: Based on the above configuration, modify the configuration of R2 : Configuration command [Note] If the router receives a tagged packet and the top tag cannot be found in the local LFIB , the CISCO IOS will discard it. ISO 10589 requires that the hello data be padded to the MTU size of the output interface , which means that the same MTU is usually used at both ends of the adjacency relationship. Topology environment description: Max_reservable_bw_sub: 0 ​​(kbps) *Aug 18 09:06:02.699: Path Latency (microseconds):0 Manual re-optimization 10.1.13.3 Min unit=0 bytes, max pkt size=2147483647 bytes Mpls traffic-eng tunnels ip rsvp bandwidth Ip address 1.1.1.1 255.255.255.255 Router ospf 1 ! Ip address 2.2.2.2 255.255.255.255 CSNP Interface Tunnel0 O 204 Pop Label 5.5.5.5/32 0 Tu0 point2point MAC/Encaps=14/18, MRU=1500, Label Stack{304}, via Et0/1 0E00003017000E00003016108847 00130000 Collect IP routing information obtained through other routing protocols FastEthernet0/0 via high priority queue IGP metric: 1 Pop Label 5.5.5.5 Tun ID: 0 Ext Tun ID: 1.1.1.1 FRR intf/label Untagged *Aug 18 09:06:07.919: ADSPEC type 2 length 48: Ip address 10.1.34.4 255.255.255.0 Bytes tag switched Ip explicit-path name R2R4 enable next-address 10.1.12.2 Reservable Bandwidth[7]: Network 10.1.45.4 0.0.0.0 area 1 Label space *Aug 18 09:06:02.699: EXPLICIT_ROUTE type 1 length 52: Signalling: connected Holding timer : Hold time, default 30S 0 kbits/sec *Aug 18 04:37:06.239: Tun Dest: 5.5.5.5 Tun ID: 0 Ext Tun ID: 1.1.1.1 The area address groups configured on the router are listed. It only appears in non-pseudo nodes Session Current LSP: The tunnel configuration of R2 is modified as follows: Interface fas0/0 *Aug 18 09:06:07.919: version=0 length in words=10 Do not advertise routes leaked from other levels *Aug 18 04:37:06.239: Controlled Load Service break bit=0 service length=0 Ip address 10.1.45.4 255.255.255.0 We see that the main content of the pseudo-node LSP is the IS connected to this pseudo-node . Look at the neighbors of isis again : N/P Going is the tunnel . therefore: Mpls ldp session protection for 1 duration 30 Bytes tag switched Tunnel mpls traffic-eng path-option 10 dynamic Brief introduction to the work process ES-IS Routing Protocol Experimental needs The attribute tag is a 32-bit field, which is described in detail later. Interface loopback0 Interface FastEthernet0/0 0x8973 The configuration of R3 is as follows: Network 10.1.34.3 0.0.0.0 area 0 R1#sh mpls traffic-eng topology 1.1.1.1 Therefore, R1 will only use R4 's label mapping for 3.3.3.3 , that is, use label 404 to send the label packet to 3.3.3.3 . Ip address 4.4.4.4 255.255.255.255 P2P Links: Multiacces Links: 75000 kbits/sec, R1(config)#interface fa0/0 TLV Tib entry: 3.3.3.3/32, rev 13 *Aug 18 09:06:02.699: Tun Dest: 5.5.5.5 Tun ID: 0 Ext Tun ID: 1.1.1.1 Router(config)# mpls ldp session protection for acl-peer duration sencondes Let's look at the picture. If R1 to R6 want to establish a TE tunnel , which is the optimal path, and the bandwidth requirement is 30Mbps , what is the calculation process? First of all, thanks to the flooding of link state information in the zone, " OSPF or IS-IS for MPLS TE extensions ", Router# mpls traffic-eng reoptimize *Aug 18 09:06:02.699: Tun Sender: 1.1.1.1 LSP ID: 247 Regular area (non-backbone area) Then the LSR pushes the IP packet into a tag header, tags 204 , and forwards it out from the F0/0 interface. In CISCO IOS , CEF switching is the only IP forwarding mode that can be used to mark messages . Therefore , CEF must be enabled on the router when MPLS is enabled . IS reachability Tunnel mpls traffic-eng priority 7 7 tunnel mpls traffic-eng bandwidth 20000 Tspec: ave rate=2000 kbits, burst=1000 bytes, peak rate=2000 kbits RSVP Resv Info: Configure the tunnel to use a statically specified path or a dynamic path calculated through the TE topology database. Fa0/0 Destination-based load balancing is actually achieved by HASHing the destination and source IP addresses . In other words, it is actually based on source and destination address pairs for load balancing. Set-overload-bit suppress interlevel redistribute connected level-1 Record Route ( RRO ) Redistribute connected level-1 !! Redistribute the local direct loopback 2.2.2.0/24 to level1 redistribute isis ip level-2 into level-1 route-map test The configuration of R1 is as follows: Mpls traffic-eng tunnels mpls label range 400 499 0x00000026 Configuration example 1 : 0/0/1 Create a TE tunnel on R1 , the source is its own loopback0 , and the destination is 4.4.4.4 of R4 . Tunnel mpls traffic-eng bandwidth 60000 Filter the inbound label bundles advertised by LDP neighbors. Intermediate LSRs - Intermediate LSRs receive an incoming labeled packet, perform an operation on it, switch the packet, and send the packet on the correct data link. C 10.1.123.0 is directly connected, FastEthernet0/0 i*L1 0.0.0.0/0 [115/10] via 10.1.123.3, FastEthernet0/0 Experimental procedure Network 10.1.12.1 0.0.0.0 area 0 Interface eth0/0 Next Hop TLV135 : Extended IP Rechability LSP Database LSP database Ip address 4.4.4.4 255.255.255.255 *Aug 18 04:37:06.239: Incoming PathError: !!R2 sends a patherror message to R1 0x0000000C Environmental description It can prevent the structure of the core transmission network from being exposed due to TTL=0 return error message We can define the priority of the TE tunnel ! Tunnel mpls traffic-eng priority 6 6 Ip prefix-list test seq 5 permit 5.5.5.0/24 route-map test permit 10 Experimental procedure (Tunnel0) Destination: 5.5.5.5 4 10.1.45.5 0 msec * 0 msec 6bits POP is the TTL of the top-level tag minus 1 and then pops up. The new TTL value is written to the top-level tag of the outbound data. *Aug 18 09:06:07.919: TE metric is a parameter used to build a TE topology that is completely different from the IP topology (although by default it is equal to IGP metric ) Current LSP: Do not need to explain it again? At R4 , R4 pops the top label and forwards the packet to R5. We see that the main content of the pseudo-node LSP is the IS connected to this pseudo-node . Look at the neighbors of isis again : Interface tunnel0 !! TE tunnel It can prevent the structure of the core transmission network from being exposed due to TTL=0 return error message Et0/1 Interface Tunnel0 Mpls traffic-eng router-id loopback0 mpls traffic-eng area 0 Tag or VC ! 75000 kbits/sec, Attribute tag and affinity attribute IS-IS *Aug 18 11:26:02.546: Verify that you receive the LDP Hello from the other party. Mpls traffic-eng tunnels mpls label range 300 399 ! Then R1 will use the IGP of Metric , and ignore R2 on the configuration of the physical interface adminnitration-weight , so after the entry into force of the above command, go R1 view on the tunnel 's path weight , it turned into a 3 . Router(config)# mpls ldp neighbor [vrf vpn-name] ip-addr targeted [ldp | tdp] Meet the FIB , LIB , and LFIB tables *Aug 18 04:37:06.239: peak rate =250000 bytes/sec The configuration of R3 is as follows: Further analysis of the metric problem. We focus on 55.55.55.55 , after the basic configuration above, currently in the routing table of R2 Lost LSPs can be requested by PSNP to see an example: System ID 10.1.12.1 Run OSPF on the entire network to announce direct connection and loopback interface. The configuration of R2 is supplemented as follows: Ip route 5.5.5.5 255.255.255.255 Tunnel0 Is-type level-2-only *Aug 18 04:37:06.239: Flags: 0x0 MPLS is a forwarding technology based on packet labeling MTU implicit check MPLS VPN Architecture Volume 2 Activate LDP on all devices. To facilitate observation, specify the label range for each device . For example , the label range of R1 is 100. Fast tag rewrite with Fa0/0, 10.1.12.2, tags commit: {203} via 10.1.12.2, FastEthernet0/0, 0 dependencies 303 10.1.23.2 LSP Head, Tunnel0, Admin: up, Oper: up Src 1.1.1.1,cisco networking academy, Dest 5.5.5.5, Instance 30 Fast Reroute Protection: None Next Hop ! Link state information IGP itself supports !!! ISO10589 Bytes tag Class of data – The FEC which is mapped onto it After all the LDP routers have sent the label bundles to each other, everyone gradually builds their own LFIB . Each hop LSR that the TE tunnel needs to traverse is added to an ERO . This is an ordered list of interface IP addresses, each LSR 1096 Next-address 10.1.12.2 RFC3209 RSVP-TE Extensions to RSVP for LSP tunnels describes the extension of MPLS TE function by RSVP protocol . Reservable Bandwidth[7]: 10.1.34.3 Like the above figure, it is very easy for traffic to go unilaterally. The R1-R3-R4-R5 link does not carry traffic. It may be possible to adjust the link such as cost to make the following link available. The method may bring problems to other traffic while adjusting. In general, the IP traffic engineering guides the traffic to a relatively simple one. It is nothing more than the ospf protocol that manipulates the cost by using the characteristics of the protocol itself, or manipulates the path attributes like BGP , or through policy routing. Control.