ccna exam questions 2014

ccna exam questions 2014

In a typical network design, multiple independent Level1 areas are connected through a backbone network, and the backbone network is composed of routers with Level 2 routing functions. The Level1-2 router has two independent link state databases that support Level1 and Level2 routing , respectively . The configuration of R4 is as follows: Tib entry: 1.1.1.1/32, rev 2 [115/20] via 10.1.24.2, Serial0/0 Tunnel mode mpls traffic-eng Mpls traffic-eng tunnels ip rsvp bandwidth Interface Tunnel0 Targeted Hello 2.2.2.2 -> 4.4.4.4, active System ID The forwarding of IP packets in each hop router is based only on the destination address. Implicit empty label *Aug 18 11:31:44.598: 1.1.1.1:0 4 10.1.12.1 1060 msec 984 msec 1080 msec Type 1 length 52: Opaque ID: 0 Mpls traffic-eng tunnels ip rsvp bandwidth !! Neighbor's SNPA , the interface MAC of the other party in the LAN IP protocol TLV . If a router does not recognize a TLV , it will be ignored. 1.1.1.1/32 R1#traceroute 55.55.55.55 Router ospf 1 vrf VPN-A redistribute bgp 2345 subnets network 10.1.56.5 0.0.0.0 area 0 *Aug 18 04:37:06.243: Tun Dest: 5.5.5.5 Tun ID: 0 Ext Tun ID: 1.1.1.1 The interface is assigned a new metric value; Reservable Bandwidth[4]: Subdivided into Area , roughly similar IP subnet Then you need the top-level tag, which looks at the next hop. The next hop is 5.5.5.5 , so be sure to find the 5.5.5.5 tag. As we have seen from the routing table, at this point R2 goes to 5.5.5.5 and actually enters the TE tunnel , then: Tib entry: 10.1.23.0/24, rev 8 Level1 : Relative to the concept of a single area, consists of L1 routers in this area, and its routing information is published to Backbone . Targeted Hello 2.2.2.2 -> 4.4.4.4, active Needless to say this? Record Route: NONE Configuring multiple NETs for a single IS-IS process 959 Interface FastEthernet0/0 Mpls traffic-eng tunnels ip rsvp bandwidth Multicast packets belonging to a specific multicast group An IP address. Look again, now looking at the traffic with the source of 10.1.35.55 for 1.1.1.1 , we found that R3 uses another equivalent path, that is, it goes out from the F0/0 port. This is based on the meaning of the source address pair. ! i L1 i L2 Designated IS ( DIS ) ! ISIS for NBMA support network is still flawed, as in the previous experiment demonstrates, if it is run on a Frame Relay main interfaces ISIS , or P2MP run on sub-interfaces ISIS , then you must ask PVC full-mesh, otherwise, the route study Not normal, but even if the PVC is fully interconnected, there are hidden dangers. If a PVC fails, routing will still have problems. Ip router isis 0 kbits/sec Ip unnumbered Loopback0 Environmental description 0 kbits/sec The trick of traditional IP routing: Set-overload-bit on-startup <5-86400 sencondes> Lists the Layer 3 protocol supported by the integrated IS-IS protocol. Currently only CLNP OutLabel : FastEthernet0/0, 200 RSVP Signalling Info: RFC 2370 describes an extension of OSPF that defines three new LSAs . These LSAs are called sluggish LSAs ( opaque LSAs ) and their differences are limited to the extent of propagation. These LSAs can accurately provide the information required by MPLS TE to OSPF : Configure targeted-hello accept acl C 1.1.1.0 is directly connected, Loopback0 10.0.0.0/24 is subnetted, 2 subnets The configuration of R3 is as follows: ! In CISCO IOS routers, IOS cannot automatically allocate bandwidth-based link (interface) metrics. Regardless of the bandwidth of the link, the default IS-IS metric for all interfaces is 10 , of course you can modify it. The maximum metric for a full path is 1023 . Of course, the IETF has extended the default metric . SRM ( Send Routing Message ): Send routing information message Next Hop Used to confirm and request link status information Interface eth0/0 Configure the tunnel to use a statically specified path or a dynamic path calculated through the TE topology database. In the IGP (such as OSPF or ISIS configuration) of the routing process. This command sets the TE router 's routerID Router(config)#interface tunnel0 TE Metric : Administrative weight Data plane : Data forwarding based on tags Take a look at the routing table for R1 : Tunnel mpls traffic-eng forwarding-adjacency R3 configuration is as follows The overload router participates in the calculation as the last hop route. Use set-overload-bit to manually set the overload bit. Tunnel mpls traffic-eng forwarding-adjacency 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 Outgoing tag or VC value 75000 Next-address loose 10.1.45.5 The configuration of R2 is as follows (all configurations are omitted from the configuration of interface IP ): Tunnel mpls traffic-eng bandwidth 2000 Mpls traffic-eng tunnels mpls label range 300 399 Route-map test permit 10 router isis Untagged O In a network running MPLS , you can set these two paths to different LSPs and use different labels. On R1 , R6 and We see the above output, R1 , R2 , R3 all generate LSP , and the asterisk entry is issued by R1 itself. In addition, there is a special Ip address 1.1.1.1 255.255.255.255 RSVP and label (Link ID) Network/subnet number: 2.2.2.2 (Link Data) Network Mask: 255.255.255.255 Number of MTID metrics: 0 - Mpls traffic-eng signalling advertise implicit-null [acl x] Next Hop Ip vrf forwarding VPN-A In operational contexts , a tunnel can be removed from one path and palced onto another. (Tunnel0) Destination: 5.5.5.5 880 When the router initiates IIH , the circuit type in the header is set according to the configuration we have made : L1 , L2 or L1-2 . OSI PDU Downstream on Demand max hop count: 255 Downstream on Demand Path Vector Limit: 255 LDP for targeted sessions R1#show ip route 5.5.5.0 IPv6 , then it must publish routing information with this NLPID value. After the above configuration is completed, there is one more unidirectional direct link to R5 on R2 . This link will directly participate in the routing calculation of R2 itself. The overall result is that there are now three straight connectors on R2 : eth0/0 , eth0/1 , tunnel0 . LDP ID election is the same as OSPF routerID PATH is used to establish and maintain, retain Election order of DIS lab environment Based on the above configuration, modify the configuration of R2 : Use the clns host command in global configuration mode to establish a mapping of hostnames to NSAP addresses. In this way, in the link state database, LSP It can be seen that ES-IS plays a role in the CLNS network environment as if the ICMP , ARP and DHCP protocols in the IP network work together. Basic command O 2.2.2.2 [110/2] via 10.1.23.2, 00:09:07, FastEthernet0/0 *Aug 18 09:06:02.699: SENDER_TSPEC type 2 length 36: Router ospf 1 L1 / L2router with the set attached-bit route-map associated with a route-map test deny the route-Map , it. Local binding: tag: 101 Network 10.1.23.2 0.0.0.0 area 0 mpls traffic-eng router-id loopback0 mpls traffic-eng area 0 In CISCO IOS routers, IOS cannot automatically allocate bandwidth-based link (interface) metrics. Regardless of the bandwidth of the link, the default IS-IS metric for all interfaces is 10 , of course you can modify it. The maximum metric for a full path is 1023 . Of course, the IETF has extended the default metric . You can see Path weight=3 . How did this 3 come from? Because R1 establishes a tunnel to R4 , then R1 reaches R4 (note that it is not Record Route: NONE Note: a FEC can contain multiple streams, but not a stream of a FEC , such as looking at a host Sina website, which is a stream and looking at Sina's video, which in turn is a stream, the two streams When Sina sends to a remote host, the path should be the same, so one FEC has multiple streams, but each stream does not belong to a separate FEC. Experimental configuration !! Re-release the local direct loopback 2.2.2.0/24 to level1 Config Parameters: Router , thus maintaining two independent L1 link state databases and L2 link state databases. Then, if there is a router in the backbone that is not connected to the L1 router , it can be configured as an L2 router . lab environment 303 10.1.12.2 Ll Router , maintains first a layer LSBD , by default, L2 of the LSP is not flooded over, and therefore L1 router 's LSDB Calculated. In the figure above, the red path is calculated by CSPF . The label mapping message advertised locally is meaningful to the local . The label corresponding to the same FEC advertised from different interfaces is different. Tunnel mpls traffic-eng autoroute metric absolute y We can define the priority of the TE tunnel Of course, not the remote tag in LIB will be used. We also need to combine the FIB table to get the next hop information about the prefix. Finally form the LFIB table: Is-type level-1 Record Route: NONE Verify that you receive the LDP Hello from the other party. Provide a loop-free network Outgoing My Address: 10.1.12.1 10.1.34.3 10.1.34.4 Protction the Node (Node Protection) I/E Record Route: 2.2.2.2(200) 4.4.4.4(403) If the payload of the MPLS is not an IPv4 packet, load balancing will be performed by looking at the value of the label at the bottom of the bottom. The PATH message is sent to the end of the hop by one hop; the RESV message is sent to the headend router in the opposite direction. The R2 re-released 2.2.2.0 external route is still there; the inter-area route is gone, except for a R2 local direct connection of 24.0 ; in addition, R1 still does not use R2 as the next hop of the default route. Globally activate MPLS TE tunnel and set MPLS label space Area Address: 49.0001 Routing entry for 5.5.5.0/24 Some SPFs are restricted for inter-domain and external routing, and any inter-domain link turbulence caused by smaller areas and hierarchical topology extensions leads to complete Mpls ldp router-id loopback0 mpls label range 100 199 interface fast0/0 Interface eth 0/1 TOS 0 Metrics: 10 The configuration of R2 is as follows: Router(config-router)# max-area-address xx R6#traceroute 5.5.5.5 soure 6.6.6.6 Routers in the network must identify all in order to perform appropriate operations Pop tag Name: R2-PE1_t0 Status: Te use TE metric default is this ...... ...... Traditional TTL operation 75000 R1#sh ip os mpls ldp interface fa0/0 55000 By default, the OSPF hold time ( dead-interval ) is Local tag 3.3.3.0 [115/20] via 10.1.123.3, FastEthernet0/0 10.0.0.0/24 is subnetted, 3 subnets 1096 55000 ! [3]: 75000 kbits/sec Take a look at the routing table for R1 : Pop tag Ciphertext interface authentication By default, if the synchronization is not completed, the IGP does not explicitly know the time to wait before establishing the adjacency relationship. Record Route: NONE Then just fill in the configuration on R2 . I won't go into details here. Interface eth0/1 We see that although the tunnel is established between R3 and R5 , this tunnel is invisible to R1 . In the eyes of R1 , only the OSPF links are OSPF cost ,ccna exam questions 2014, so R1 goes to R6 , which is definitely The above link is preferred because the cost is small. 0xA538 In RFC5250 In been described herein: A neighbor Capable IS-opaque and only IF The IF IT sets-O 'bit in the Options The ITS Database Field of the Description packets; The-O' bit the NOT SHOULD BE SET When ignored and the MUST BE Configured in OSPF process mode, this command activates MPLS TE in a specific area. The OSPF adjacency relationship will not be established until the LDP session is successfully established or the "synchronization hold time" expires . The synchronization here indicates that the local label bundle has been sent to the LDP peer through the LDP session . However, if A is activated on the router and MPLS LDP-IGP is synchronized, and there is only one link between A and B , and no other available path to B , the OSPF adjacency will never be established. Because OSPF waits for the LDP session is established, but the LDP session can not be set up because A can not learn in its routing table B of LDP routerID route, so enter an infinite loop, OSPF and LDP adjacencies will never Unable to create. In this case, LDP-IGP synchronization will activate the OSPF adjacency unconditionally , so that the link will advertise the largest.The metric value until the synchronization is complete.