ccna test prep questions

ccna test prep questions

Remote binding: tsr: 2.2.2.2:0, tag: imp-null remote binding: tsr: 3.3.3.3:0 , tag: 301 Interface fast 1/0 Remove: The top label is removed. The forwarding of the message depends on the remaining tags in the tag stack, or it is forwarded as an unlabeled message. 1144 Default change threshold (bandwidth occupancy): 1.1.1.1 4 10.1.12.1 1060 msec 984 msec 1080 msec 0/0/0 Lists the list of directly connected IP address prefixes Mpls traffic-eng tunnels ip rsvp bandwidth Mpls traffic-eng tunnels mpls label range 500 599 10.1.12.2 O 2.2.2.2 [110/2] via 10.1.12.2, 00:00:37, FastEthernet0/0 Now we will complete the following configuration on R2 : The label is incorrect. This situation only occurs when the IGP is OSPF . Because if the loopback is used as the router-id of the ldp and it is not 32 -bit, OSPF will automatically issue the 32 -bit loopback address. Causes the label to be assigned an error. IDP and DSP can be borrowed from the concept of IP inside. IDP has something like the main network number. DSP has something like subnet number and host IP . Of course, the meaning of this IDP is relatively complicated. See The following figure: Ip explicit-path name R2R4 enable next-address 10.1.12.2 In the IGP (such as OSPF or ISIS configuration) of the routing process. This command sets the TE router 's routerID Router# mpls traffic-eng reoptimize LSPID LSP Seq Num LSP Checksum LSP Holdtime ATT/P/OL RFC1195 *Aug 18 09:06:02.699: Token bucket fragment (service_id=1, length=6 words Router(config)# mpls ldp targeted-hello holdtime x interval y Alternatively, you can configure the following command on the tail router: 1bit Signalling: connected Complete the routing information exchange between the area and the backbone where it is located, and assume both the responsibility of L1 and the responsibility of L2 . Integrated IS-IS ( IS-IS ) enables the IS-IS protocol to propagate routing information for protocols other than CLNP . IGP Area[1] ID:: ospf area 0 System Information:: However, not all messages with the same label belong to one FEC , because the EXP values ​​of these messages may be different and may be performed differently, so they may belong to different FECs . Ip address 10.1.255.1 255.255.255.255 10.0.0.0/24 is subnetted, 4 subnets The configuration of R2 is as follows: It can prevent the structure of the core transmission network from being exposed due to TTL=0 return error message Router(config)# mpls ldp targeted-hello holdtime x interval y Pop tag LSP Neighbor 5.5.5.5 send-community extended exit-address-family Router(config)# mpls ldp targeted-hello accept from acl 10.1.12.2 2.2.2.0 [115/20] via 10.1.123.2, FastEthernet0/0 3.0.0.0/24 is subnetted, 1 subnets *Aug 18 04:37:06.239: IS Hops:1 Router(config)# mpls ldp neighbor xxxx labels accept acl Bandwidth: 2000 kbps (Global) Priority: 7 7 Affinity: 0x0/0xFFFF Metric Type: TE (default) ID: path option 10 [1] HELLO PDU (ESH , ISH and IIH) Create a TE tunnel on R1 . The source is its own loopback0 . The destination is 5.5.5.5 for R5 . Interface Ethernet0/0 Ip address 10.1.56.5 255.255.255.0 Network 10.1.12.1 0.0.0.0 area 0 MPLS TE using type 10 of LSA to a region within MPLS TE work. Priority 4 : 9375000 i* L1 R1#show mpls ldp discovery detail Router ospf 1 " MPLS technology architecture."*Aug 18 04:37:06.239: version=0, length in words=7 Mpls traffic-eng tunnels mpls label range 300 399 InLabel : - Reservable Bandwidth[6]: Protect lsp path: 10.1.12.1 10.1.12.2 Redistribute isis ip level-2 into level-1 route-map test ! 10.1.35.55 -> 1.1.1.1 : FastEthernet0/0 (next hop 10.1.23.2) The configuration of R1 is as follows ( R2 does not open area password temporarily ): Ip address 3.3.3.3 255.255.255.255 Interface Tunnel0 This inbound label packet, with a label value of 203 , indicates in the LFIB table of R2 that 203 needs to be exchanged to 300 and then dropped to the next hop. The routing table of R2 is as follows (omit direct route): CSPF ( Constrained Shortest Path First ) SPF algorithm with constraints 10.1.34.4 4.4.4.4 The command to define an Explicit path is as follows: Access-list 1 permit 3.3.3.3 Ip address 10.1.34.3 255.255.255.0 Frame-relay map ip 10.1.123.3 103 broadcast frame-relay map clns 102 broadcast We have found, R6 originating packet is IP , to the R4 ,ccna test prep questions, 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 : Mpls traffic-eng tunnels ip rsvp bandwidth 0 kbits/sec IDI Initial Domain Identifier , a variable-length initial domain identifier that identifies a subdomain under AFI My Address: 10.1.12.1 Interface fast0/0 If the bandwidth parameter is not followed by the command, the "reservable bandwidth" of the interface defaults to 75% of the physical bandwidth of the interface . Router ospf 1 mpls ldp sync Interface Loopback0 ISO 8348/Ad2 The two new TLVs are: IS 1921.6800.1024. 33M The forwarding behavior of such IP packets may cause link transitions in some networks, while other links have a low probability of use. Bw[5]: We see that there are two layers of labels here. Therefore, R2 pushes the original IP packet into a layer of VPN label 505 and pushes in two layers of labels 305 403 . It is noted here that the label 403 is the LDP label assigned by R4 with the prefix 5.5.5.5/32 , which is passed to R2 through the targeted LDP connection . And 305 is the label that R3 assigns to the TE tunnel through RSVP . Note: LDP or TDP only generates labels for routing entries of the IGP protocol, and does not generate labels for BGP routing entries. R3.01-00 General Parameters break bit=0 service length=8 55.55.55.55 [110/31] via 5.5.5.5, 00:00:01, Tunnel0 R2 configuration is as follows R1.00-00 FastEthernet0/0, Src IP addr: 10.1.12.2 Addresses bound to peer LDP Ident: Fa0/0 55000 3.3.3.0/24 Network 10.1.45.4 0.0.0.0 area 0 mpls traffic-eng router-id loopback0 mpls traffic-eng area 0 No mpls ip propagate-ttl [ forwarded | local ] TOS 0 Metrics: 10 Next, let's take a look at the details of these LSPs : (Tunnel0) Destination: 5.5.5.5 Then on R1 to see the tunnel , his TE metric becomes 102 . A Forwarding Equivalence Class (FEC) Remote binding: tsr: 2.2.2.2:0, tag: imp-null tib entry: 10.1.13.0/24, rev 8(no route) In this way , when the IP packet is tagged on the border device, the TTL value in the original IP header is not copied , but a 255 value is used instead. Address-family vpnv4 neighbor 2.2.2.2 activate The re-addressing process is similar to zone merging and separation, except that during re-addressing, some or all of the router's zone prefixes need to be cleared, with new ones. If the payload of the MPLS is an IPv4 packet, load balancing is implemented by hashing the source and destination IP addresses of the IPv4 packet header . Alternatively, you can configure the following command on the tail router: Link state information IGP itself supports The TTL diffusion process of the IP- label packet is described above . Now let's look at the TTL diffusion process from label to label . LSP Seq Num LSP Checksum LSP Holdtime If you want the penultimate hop router to recognize the "explicit empty tag" advertised by the tail router as "explicit empty tag", then you can The path calculation of the MPLS TE tunnel requires relevant information to be performed. Then we need to use a link state routing protocol to flood the link information to all routers running TE in the network . After collecting the information, the TE router establishes its own MPLS TE Database .