ccna exam past papers

ccna exam past papers

Ip rsvp bandwidth We see that although the tunnel is established between R3 and R5 , this tunnel is invisible to R1 . In the eyes of R1 ,ccna exam past papers, only the OSPF links are OSPF cost , so R1 goes to R6 , which is definitely The above link is preferred because the cost is small. 75000 LAN on the MAC or the X.25 , FR or ATM in the virtual circuit ID Interface The LSP overload-bit generated by this router is set. This will cause the router to not be used by other routers as the next hop to any destination, except for its locally connected network segment. This is generally used when the router is a leaf node, that is, the end of the network, directly connected to the user. Mpls ldp igp sync holddown 5000 Based (internet per-Platform ) compared to the label space-based interface ( per-interface ) security label space to lower Mpls ip AS Manually reoptimize We see that after the BGP neighbor relationship is up , R2 immediately triggers an LSP , and the overload is set before the LSP is cleared . Local binding: tag: imp-null Independent control mode : Independent Control LDP discovery sources: Interface eth 0/1 Interface fast1/0 OSI terminology Debug isis update on R2 ! *Aug 18 09:06:07.919: version=0, length in words=7 Label space : Label Space End host. For example , the ISO CLNP workstation searched by the ES-IS protocol . Mpls ldp neighbor 3.3.3.3 targeted ldp Global Pool Sub Pool Fspec: ave rate=20000 kbits, burst=1000 bytes, peak rate=20000 kbits 12 The interface IP of R3 is 10.1.23.3 . The average allocated traffic on the interface. Mlps ldp neigbor [vrf vpn-name] ip-addr password [0-7] pswd The existence of the established tunnel has changed. The network environment at this moment is as follows: An LDP packet carries multiple label mapping messages. Virtual link Advertising Router: 1.1.1.1 LS Seq Number: 80000001 R3 0xA538 Network 10.1.34.4 0.0.0.0 area 0 LDP discovery sources: TCP connection: 2.2.2.2.61914 - 1.1.1.1.646 Ip address 4.4.4.4 255.255.255.255 Interface fas1/0 Version : value is 1 (Link ID) Network/subnet number: 2.2.2.2 (Link Data) Network Mask: 255.255.255.255 Number of TOS metrics: 0 2.2.2.2 [110/65536] via 10.1.12.2, 00:00:47, FastEthernet0/0 300 Metric: 10 If the payload of the MPLS is an IPv6 packet, the load balancing is performed according to the source and destination addresses in the IPv6 header. IP subnet Interface fast 1/0 The loopback0 address space of all devices is xxxx/32 , and x is the device number. I don't want L1-router to generate this default route, or more rigorously, we don't want L1\L2 router to press att , the method is Type 1 length 8 : Contains the tunnel's prioritization, hold priority, and some flags 10.1.45.5 5.5.5.5 Certification Information 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. CSNP 1194 Interface eth 0/0 The label mapping message that is advertised locally is meaningful to the global . The labels corresponding to the same FEC advertised from different interfaces are the same. Neighbors should use PSNP to confirm this LSP Interface eth0/0 Flags: 0x0 *Aug 18 09:06:07.919: version=0 length in words=10 It periodically changes tunnel bandwidth(BW) reservation based on traffic out tunnel. Point2 Address-family ipv4 vrf VPN-A no synchronization Address-family ipv4 vrf VPN-A no synchronization LDP adjacency establishment process The two important thresholds in the LSP remaining time field are: LSP maxage and LSP refresh interval ISO10589 Show ip cef detail Show tcp brief Mpls traffic-eng tunnels mpls label range 200 299 Mainly two functions: Network 10.1.23.3 0.0.0.0 area 0 Router isis PATH/RESV The interface is assigned a new metric value; Name: R1_t0 Status: Create a " pseudo-node LSP " in the broadcast subnet and advertise all the routes in the subnet (the LSP is similar to the LSA ) Remote binding: tsr: 2.2.2.2:0, tag: 200 State Error Node: 10.1.12.2 Error Code: 25 (Notify) Local tag ! Mpls label rangempls label range 100 199 interface fa0/0 Election DIS . In this network, the DIS will generate and flood the new pseudo-node LSP on each of the routing layers it participates in (whether L1 or L2 ) and on each LAN it is connected to . Each router on the LAN establishes adjacency with all other routers and DISs , and does not elect to back up the DIS router. The elected DIS does not guarantee that it will always be DIS . Moreover, it is not necessary to maintain the matching time of both parties when establishing the adjacency relationship. Ip address 10.1.23.3 255.255.255.0 Bits are used to advertise the virtual link, thereby signaling the presence of the virtual link to the level1 router for inter-area data forwarding. Of course, this feature is extremely useless, and support on CISCO IOS , you have to check the relevant documentation. Mpls traffic-eng tunnels ip rsvp bandwidth 0xCC 3.3.3.3/32 Label 0 explicit null label Area Address: 49.0001 Since the IP packet is generated on the initial router, the CEF table is searched . With the " show ip cef detail " command, you can see from the output whether the route is pushed into the label. The distribution label is based on The prefix in the CEF table is assigned. Net 49.0001.0000.0000.0002.00 Ip router isis !! TE tunnel The PATHTear packet is similar to the PATH except that it is sent when the TE tunnel LSP created by the headend router needs to be removed . For example, the tunnel interface is manually shut down . NSAP address re-addressing 0x00000014 The above output is the opaque-area LSA of type10 flooded by each router in area0 in this environment . You can take a closer look at it, for example, look at R1 itself to generate LSA10 : Tunnel destination 4.4.4.4 tunnel mode mpls traffic-eng Traffic using traffic engineering uses source-based routing instead of routing based on destination IP address 0 kbits/sec After completing the above configuration, we can check that the routing network is now interoperable. Interface loopback0 ! In order to ensure the simplicity of the experimental environment first, I will ignore the existence of the R4 and R4 direct links. When you don't exist, you will be there. Mpls label rangempls label range 300 399 interface fa0/0 10.1.12.2 *Aug 18 09:06:07.919: SENDER_TEMPLATE type 7 length 12: Tunnel mpls traffic-eng priority 6 6 *Aug 18 09:06:02.699: Tun Sender: 1.1.1.1 LSP ID: 247 *Aug 18 09:06:02.699: TIME_VALUES type 1 length 8 : Next, let's look at the isis database of R1 : MPLS and Tag switching In a broadcast multi-access network, a router is elected as a DIS , and a peer-to-peer network does not require a DIS. Administrator-weight , and only the IGP metric is used to calculate the shortest path of the tunnel . Reservable Protocols support Mpls ldp discovery targeted-hello accept from accept-ldp Mlps ldp neigbor [vrf vpn-name] ip-addr password [0-7] pswd Network 10.1.12.2 0.0.0.0 area 0 Mpls traffic-eng tunnels mpls label range 200 299 Mpls traffic-eng tunnels mpls ip Receives packets from other L2 routers in the area and forwards the packets to the L2 routers of other areas according to the destination address (or to the L2 router of the same area ). Receive packets from L2 routers in other areas and forward the packets according to the destination address. R1 , R2 , R3 , and R4 are in Transit AS 1234 . The IGP protocol running in the AS is OSPF. Access-list 1 permit 5.5.5.0 route-map test permit 10 Neighbor 2.2.2.2 update-source Loopback0 Redistribute ospf 1 vrf VPN-A match internal external 1 external 2 Tspec: ave rate=0 kbits, burst=1000 bytes, peak rate=0 kbits RSVP Resv Info: Metric: 10 State ! *Aug 18 09:06:02.699: 10.1.24.2 (Strict IPv4 Prefix, 8 bytes, /32) *Aug 18 09:06:07.919: Token bucket fragment (service_id=1, length=6 words R3#sh mpls forwarding-table 1.1.1.1/32 Local label info: global/16 Label location [1]: 75000 kbits/sec 0/0/0 Fa0/0 Tag request object *Aug 18 04:37:06.243: Incoming ResvTear: Reservable Bandwidth[2]: Ciphertext interface authentication RRO Rl , R2 , R3 , R4 running the OSPF , declaring a straight connector, and Loopback interfaces, Loopback port IP of XXXX / 32 , X Both are link state routing protocols, which require routers in the area to exchange link state information, and link state information is collected in the link state database. Hello interval: 5000 ms; Transport IP addr: 1.1.1.1 LDP Id: 2.2.2.2:0; no host route to transport addr Let's look at an example: 0x0000000C lab environment Create a TE tunnel on R1 , the source is its own loopback0 , and the destination is 4.4.4.4 of R4 . The label header has a total of 32 bits and contains the following fields: *Aug 18 11:26:02.546: 100 1178 About LDP and IGP synchronization Device Internet segment 10.1.xy.0 / 24 , where xy is the device number, X small y large 3.3.3.3 LDP discovery sources: The loopback0 address space of all devices is xxxx/32 , and x is the device number. Ordered control mode : Odered Control ! Type 1 length 12: Label location Interface eth 0/0 *Aug 18 11:31:44.598: Time since path change: 10 minutes, 34 seconds Number of LSP IDs (Tun_Instances) used: 521 75000 0 kbits/sec Explicit Route: 10.1.12.2 10.1.23.2 10.1.23.3 10.1.34.3 Mpls traffic-eng tunnels ip rsvp bandwidth 10 ISO10589 18 2 TE metric: 1 RSVP Signalling Info: Interface Loopback0 Mpls traffic-eng tunnels ip rsvp bandwidth i L2 ! ! 120s LSP link state data unit Network 2.2.2.2 0.0.0.0 area 0 In this way, my network resources will be more rationally utilized. When R1 goes to 1.0/24 and 2.0/24 , traffic will be sent to different tunnels on R1 . At this moment R1 is the head end of my tunnel , and R5 is the end. The tunnel can set bandwidth requirements so that my tunnel can make more scientific and reasonable routing in the network, not just using OSPF metric for routing. The calculation of the tunnel path is done on the R1, which is the tunnel first-end router. In order to enable the head-end router to calculate the tunnel path more reasonably (not only using metric , but also participating in the path with elements such as available bandwidth and link attributes. Computation), we need to extend the link state routing protocol running in the network, in order to flood the information required for more path calculations, extended OSPF and IS-IS can accomplish this task.