ccna previous question papers pdf

ccna previous question papers pdf

R1#traceroute 6.6.6.6 !! Bandwidth requirement is 20M C 1.1.1.0 is directly connected, Loopback0 10.0.0.0/24 is subnetted, 2 subnets 0xA538 OSI terminology *Aug 18 04:37:06.239: SESSION type 7 length 16: Src 2.2.2.2, Dst 5.5.5.5, Tun_Id 0, Tun_Instance 5 RSVP Path Info: ! Note that this 303 obviously, is R3 assigned to this allocation result and then to R4 , R4 is with R3 label assigned to pressure to Router isis Overload : The first 3 bits if it means setting LSP originating router link state database is overloaded, memory and CPU resources has been restricted Version=0 length in words=10 Mpls traffic-eng router-id loopback0 mpls traffic-eng area 0 Lan interface MAC address For point-to-point interfaces, SNPA is the unique identifier for the circuit. For example, on the HDLC point-to-point link, the circuit ID is 0x00. 0 kbits/sec LSPID LSP Seq Num LSP Checksum LSP Holdtime ATT/P/OL *Aug 18 09:06:07.919: ADSPEC type 2 length 48: 10.1.13.3 Type 7 length 12: On the L1/L2 router , the routes of the subordinate Level1 area are summarized, so that the summary route is learned in the backbone or level2 area , and the configuration is as above. Path option 10, type dynamic (Basis for Setup, path weight 30) 75000 3B 's default metric , enough for you to stink? Label space Mpls traffic-eng router-id loopback0 mpls traffic-eng area 0 MPLS LDP-IGP synchronization configuration Interface eth 0/0 !! Activate mpls on the interface , actually activate ldp State: Oper; Msgs sent/rcvd: 112/112; Downstream Up time: 01:29:44 But if we modify the configuration on R1 : Tunnel mpls traffic-eng path-option 10 dynamic Network 55.55.55.55 area 0 L1 Then look at R2 again: Now we activate LDP for all interfaces . Then on R3 : Src 1.1.1.1, Dst 4.4.4.4, Tun_Id 0, Tun_Instance 2 RSVP Path Info: Mpls traffic-eng tunnels ip rsvp bandwidth Bandwidth: 20000 kbps (Global) Priority: 7 7 Affinity: 0x0/0xFFFF Fa0/0 Router-id 2.2.2.2 MPLS mode Mpls traffic-eng tunnels mpls label range 200 299 In this experimental test, we announced the direct-connected segments of R1-R5 and R4-R6 in OSPF . Establish mapping of data link layer address to network layer address ( CLNP address) 303 Tunnel mpls traffic-eng path-option 10 dynamic Its ingress and exgress LSRs Ip address 10.1.45.4 255.255.255.0 1 203 200 Interface eth 0/0 Mpls traffic-eng tunnels mpls label range 500 599 The database is also calculated by the CSPF algorithm, and the result is the path of the tunnel — a sequence of IP addresses. 104 My Address: 10.1.12.1 Note: To use the above command to complete conditional notifications, you need to use no mpls ldp advertise-labels first . Otherwise, the LSR advertises all label bindings. Mpls traffic-eng tunnels ip rsvp bandwidth Note that LDP does not assign labels to BGP routes by default , but we also know that BGP routes have next-hop , and this next hop is reachable for IGP routes, and LDP will be this (next hop) It is very important that the address is assigned to the route assignment label. The external route is not carried in the LSP . Link IP Address: 10.1.23.2 104 RFC 3786 10.1.12.2 [Note] Label behavior of Frame Mode R1#show isis da R1.00-00 detail Interface eth 0/0 The configuration of R1 is as follows: Interface eth0 0/0 Important difference: *Aug 18 11:26:02.546: Incoming Resv: !! R2 sends a resv message to R1 Router-id 2.2.2.2 =250000 bytes/sec 10.1.23.3 The LSP is set by ATT . Take R2 as an example. If the S1/0 port of R2 is DOWN , it loses the connection of Backbone , so R2 *Aug 18 09:06:02.699: SESSION type 7 length 16: 1.0.0.0/24 is subnetted, 1 subnets 75000 Src 2.2.2.2, Dst 5.5.5.5, Tun_Id 0, Tun_Instance 5 RSVP Path Info: Targeted Hello 1.1.1.1 -> 3.3.3.3, active, passive 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 ---------- Now create a tunnel on R1 : !! means from 13.1 to 34.3 and then to the local ( 34.4 ) PSNP For point-to-point interfaces, SNPA is the unique identifier for the circuit. For example, on the HDLC point-to-point link, the circuit ID is 0x00. Three types of TLS have been added to the extended IS-IS for TS : Pop tag Intermediate system adjacent router The third layer destination IP matches the packet with the same specific prefix. 1.1.1.0 [115/20] via 10.1.12.1, FastEthernet0/0 Ip cef Tun Dest: Fast Reroute *Mar 1 00:00:32.639: %BGP-5-ADJCHANGE: neighbor 10.1.24.4 Up All routers run OSPF Ip router isis With the following router-level configuration command: summary-address [level-1|level-2|level-1-2]. ! Interface Loopback0 After all the LDP routers have sent the label bundles to each other, everyone gradually builds their own LFIB . InLabel : - *Aug 18 04:37:06.239: Tun Dest: 5.5.5.5 Tun ID: 0 Ext Tun ID: 1.1.1.1 C 10.1.24.0 is directly connected, Serial0/0 C 10.1.45.0 is directly connected, Serial0/2 C 10.1.34.0 is directly connected, Serial0/1 i L2 10.1.123.0 [115/20] via 10.1.34.3, Serial0/ 1 The subnet point of attachments is the point at which the subnet service is provided, which is equivalent to the second layer address of the corresponding Layer 3 address ( NET or NSAP ). usually *Aug 18 09:06:07.919: SESSION_ATTRIBUTE type 7 length 16: The routing protocol in the IP network forwards the data packet according to the minimum metric principle. Complete basic IP configuration (configuration omitted) Impact of route summarization on MPLS Mpls traffic-eng tunnels ip rsvp bandwidth 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 . L1/L2 router re-releases external routes into IS-IS ( to level-1-2 ) IGP Neighbor: ID 10.1.12.2 Hostname: R1 Router ID: ! The distribution of the label is like this: On the L1/L2 router , the routes of the subordinate Level1 area are summarized, so that the summary route is learned in the backbone or level2 area , and the configuration is as above. This global command is used to modify it. After the expiration of the timer, the IGP will establish an adjacency on the link. Once the IGP adjacency is established and the LDP session has not been synchronized, the IGP will advertise the metric of the link to the maximum. *Aug 18 09:06:07.919: min unit=0 bytes, max pkt size=2147483647 bytes Ip router isis Prefix R4.00-00 Type 1 length 8 : State: Oper; Msgs sent/rcvd: 26/22; Downstream Up time: 00:09:33 The IIH is transmitted between ISs . Explicit Route: 10.1.12.2 10.1.23.2 10.1.23.3 10.1.34.4* Attribute Flags: 0x00000000 Router-id 5.5.5.5 *Aug 18 11:31:44.598: Fa0/0 R1#sh mpls traffic-eng topology 1.1.1.1 (1.1.1.1 is a local router ) Length of Value 0x00000014 Router ospf 1 10.1.23.2 In-label Out intf/label Router-id 2.2.2.2 10.1.23.0/24 Bw-based *Aug 18 09:06:02.699: average rate=250000 bytes/sec, burst depth=1000 bytes LSP Tunnel R1_t0 is signalled, connection is up Router-id 5.5.5.5 TE tunnels are distinct from MPLS LSP through which it traverses: Experiment 2 There is a unique NET By selection ( level2 routing) 2.2.2.0 [115/20] via 10.1.123.2, FastEthernet0/0 3.0.0.0/24 is subnetted, 1 subnets The bandwidth information that MPLS TE needs to advertise is: How long in msecs to wait upon flooding a down forwarding adjacentcy The existence of the established tunnel has changed. The network environment at this moment is as follows: *Aug 18 09:06:07.919: version:1 flags:0000 cksum:7A42 ttl:255 reserved:0 length:132 *Aug 18 09:06:07.919: Interface Net 49.0001.0000.0000.0003.00 The forwarding behavior of such IP packets may cause link transitions in some networks, while other links have a low probability of use. Network 10.1.34.3 0.0.0.0 area 0 mpls traffic-eng router-id loopback0 mpls traffic-eng area 0 Labels 0-15 are all reserved labels. Here are some reserved tags that have a specific role: IS-IS Level-1 Link State Database: And in R2 , the label package is pushed into a new layer of labels, the outer label is assigned by R3 ,ccna previous question papers pdf, and the inner label is assigned by R4 . 3.3.3.0 [115/20] via 10.1.34.3, Serial0/0 Remote binding: tsr: 2.2.2.2:0, tag: imp-null Does it match, verify that the password is correct, the area ID or something. Record Route: NONE Routing domain Mpls traffic-eng tunnels mpls label range 300 399 The label can be ejected on the (the penultimate hop). C only needs to find the FIB table to forward the received IP packet. In the explicit setup mode, we must specify the router that the TE tunnel needs to traverse. You can specify the TE of the router in the link. 10.1.12.2 Mpls traffic-eng router-id loopback 0 mpls traffic-eng level-1 R2 configuration is as follows 55000 LDP initial/maximum backoff: 15/120 sec LDP loop detection: off The configuration of R4 is as follows: In the routing table, R3 goes to 1.1.1.1 and uses 10.1.34.4 and 10.1.23.2 equivalent load balancing. 1.1.1.1 0 [521] All routers run OSPF Copy this value. R1# traceroute 5.5.5.5 104 Traditional TTL operation LSP Seq Num LSP Checksum LSP Holdtime 10.1.12.2 [MPLS: Label 203 Exp 0] 200 msec 84 msec 136 msec 104 The checksum calculation knows the end of the packet starting from the field after the remaining time-to-live field in the LSP . When the LSP copy is propagated between routers in the network, its checksum field is not modified. Fa0/0 AFI+IDI is used to identify the Domain Mpls traffic-eng router-id loopback0 mpls traffic-eng area 0 Let's look at an example: The above command will directly change the cost of the above calculated route to y. Area address ! ! 120s Regional separation (Link Data) Router Interface address: 0.0.0.13 Number of MTID metrics: 0 The tag value is 1 , and this tag can appear anywhere on the tag stack, except for the bottom of the stack. MC Ip address 2.2.2.2 255.255.255.255 ISO10589 Network 10.1.12.2 0.0.0.0 area 0 Interface loopback0 Src 1.1.1.1, Dst 5.5.5.5, Tun_Id 0, Tun_Instance 521 RSVP Path Info: R3#show mpls forwarding-table Explicit Route: 10.1.12.2 10.1.23.2 10.1.23.3 10.1.34.3 Router ospf 1 If you change the Path-selection metric to igp , the shortest path to the tunnel will ignore the configuration in the physical interface. Globally activate MPLS TE tunnel and set MPLS label space Options: (No TOS-capability, DC) LS Type: Router Links i*L1 0.0.0.0/0 [115/10] via 10.1.123.3, FastEthernet0/0 *Aug 18 11:31:44.598: 10.1.45.4 10.1.45.5 Ip rsvp bandwidth TOS 0 Metrics: 10 0/0/0 Inter-area IP routing changes; Routing domain Pop tag Ip router isis IGP metric: 1 Route summary L On the L1/L2 router , the routes of the subordinate Level1 area are summarized, so that the summary route is learned in the backbone or level2 area , and the configuration is as above. All interfaces of ospf area0 will automatically activate LDP. Router isis 1.1.1.1 [110/3] via 10.1.34.4, 00:53:36, FastEthernet1/0 Overview Environmental description R3#show mpls forwarding-table The label header has a total of 32 bits and contains the following fields: System ID System ID 0 kbits/sec 2.2.2.2 Fa1/0 LDP allows non-directly connected neighbors, so that neighbors discover that they do not need to rely on multicast HELLO packets, but instead use unicast packets. Time since created: 5 hours, 38 minutes 10 Router-id 6.6.6.6 By default, the cost of an IS-IS interface is 10. Next-address 10.1.24.4 The attribute tag is a 32-bit field, which is described in detail later. !! Bandwidth requirement is 20M , tunnel preemption priority and retention priority is 7 The configuration of R1 is as follows: This configuration command, R2 dependent on the autoroute characteristics calculated, associated TE tunnel port OSPF routing metric have become 9 . This is the meaning of the absolute keyword, here will not do the accumulation of cost . Basic Experiment 2 ( IS-IS ) 0x4F65 Mpls traffic-eng router-id loopback0 mpls traffic-eng area 0 It is found that a targeted session is established between R1-R3 . Now, let's come back to the Fa1/0 port of shutdown R1 . 5.0.0.0/24 is subnetted, 1 subnets Next , take a look at the Tunnel on R2 : Tunnel mpls traffic-eng path-option 10 explicit name R1toR5 DIS , initially composed of the local SystemID + unique local circuit ID . The router starts to listen to ESH , ISH , IIH at the same time . Current LSP: *Aug 18 04:37:06.239: ERROR_SPEC type 1 length 12: Run IS-IS on the entire network to announce direct connection and loopback interface. 75000 1/0/0 ! RFC 3719 ---------- 0 S 4.4.4.4 is directly connected, Tunnel0 RFC 1195 *Aug 18 09:06:07.919: 10.1.12.2 (Strict IPv4 Prefix, 8 bytes, /32) If the headend wants to remove the tunnel , send PATHtear along the tunnel path , and the received node responds to RESVtear , so the tunnel between the two points Link State ID: 2.2.2.2 Advertising Router: 2.2.2.2 LS Seq Number: 80000011 Checksum: 0xAE93 Length: 72 Domain-wide Prefix Distribution with Two-Level IS-IS The level2 route is injected into the level1 area , and these level2 routes can be summarized on the L1/L2 router . The configuration is as above. If the router performing load balancing is the inbound LSR of the IP packet , then it is easy to know that the received IP packet is IPv4. This NSAP address is still a bit longer, and it is inconvenient to use. The SystemID is mainly used to identify several attributes, such as adjacency information, LSP identifier in IS-IS database, etc. In most cases, We are more suitable for symbols that have literal meanings, such as R1 and R2 , rather than a string of numbers. So CISCO IOS provides us with a very good way: the mapping of the router hostname to the NSAP address. Essentially the mapping of hostname to SystemID . There are two methods of static mapping and dynamic mapping.