ccna online exam paper

ccna online exam paper

R1.00-00 Type 1 length 12: Router(config)#interface fast0/0 Interface Serial0/2 The LSP carries the TLV for authentication. 1178 Mpls ldp autoconfig area 0 Start LSP ID : Start LSP ID . Indicates the first LSP ID of the LSP range described in the TLV field . Route-target export 2345:2 Based on the above configuration, modify the configuration of R2 : Router ospf 1 TE Metric is equivalent to the concept of weight value, note that this is to be distinguished from IGP metric IS-IS Level-1 Link State Database: Tag or VC 75000 10 A label switched path (LSP) R2#show ip ospf database router self-originate Label Mapping message Fa0/0 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. 1.0.0.0/32 is subnetted, 1 subnets Priority 6 : 9375000 CSPF maximum arbitration Router(config)#mpls traffic-eng reoptimize timers frequency ? RFC 3373 !! TE tunnel Globally activate MPLS TE tunnel and set MPLS label space The loopback0 address space of all devices is xxxx/32 , and x is the device number. Find a LFIB , LFIB has the next hop information, so the top label is popped up and then handed over to the next hop without having to look up the FIB table again (if the label is popped, it is an IP packet). An LDP packet carries multiple label mapping messages. R4 routing table: 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. 10.0.0.0/24 is subnetted, 3 subnets Router ospf 1 mpls ldp sync Ip address 10.1.123.3 255.255.255.0 Network 10.1.45.5 0.0.0.0 area 1 10.1.23.0 [115/20] via 10.1.34.3, Serial0/0 Mpls traffic-eng tunnels ip rsvp bandwidth Reservable Bandwidth[4]: There are two ways to set the path of the TE tunnel ( Explicit explicit or Dynamic dynamic) 539 Router-id 2.2.2.2 Test the transmission process of the data stream, observe the phenomenon 3.3.3.3 [110/65537] via 10.1.12.2, 00:00:47, FastEthernet0/0 After completing the above configuration, R2 and R5 will advertise this tunnel in their own Class 1 LSA , just like a direct link. !! Outbound label 201 , which is given by R2 4 After the tunnel setup failed It periodically changes tunnel bandwidth(BW) reservation based on traffic out tunnel. Ip unnumbered Loopback0 Interface eth 0/1 3.0.0.0/32 is subnetted, 1 subnets ! R1#sh mpls traffic-eng topology 1.1.1.1 ! Therefore, in an NBMA network, such as a frame relay environment, it is strongly recommended to use the P2P sub-interface to run ISIS . *Aug 18 04:37:06.239: Incoming PathError: !!R2 sends a patherror message to R1 0 kbits/sec Network 10.1.12.1 0.0.0.0 area 0 Network 10.1.45.4 0.0.0.0 area 0 10.1.23.0/24 Mpls traffic-eng router-id loopback 0 mpls traffic-eng level-1 Current LSP: S1 / 0 port hung up, then R2 will no Level2 abutting relationship, that is, R2 and backbone or level2 area disconnected, Network 10.1.23.3 0.0.0.0 area 0 75000 The configuration of R2 is similar, so that in the TLV used for authentication in the IIH , the ciphertext after the hash is loaded, and the password is not exposed. ----------- ISO10589 Link IP Address: 10.1.12.2 10.1.23.3 [MPLS: Labels 300/403 Exp 0] 0 msec 4 msec 0 msec L1/L2 router Basic 4.4.4.4/32 *Aug 18 09:06:07.919: SESSION type 7 length 16: 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. *Aug 18 04:37:06.239: General Parameters break bit=0 service length=8 RFC 2205 Resource Reservation Protocol (RSVP) Experimental phenomena 1230 3.0.0.0/32 is subnetted, 1 subnets ESH is ES transmitted to IS of Therefore, in the above figure, if R5 sends an IPv4 packet to R3 , R3 can directly identify and hash the source and destination addresses of the Ipv4 header to implement load balancing. *Aug 18 09:06:07.919: Label description Meet the FIB , LIB , and LFIB tables 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 . Tunnel mpls traffic-eng path-option 10 dynamic Can use the default or use this command to modify Router(config-if)# bandwidth ? 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. When the change attribute (path bandwidth), using Make Before Break manner LABEL 3.3.3.0 [115/20] via 10.1.123.3, FastEthernet0/0 10.0.0.0/24 is subnetted, 3 subnets Local Label 0 kbits/sec !! 10.1.23.2 is also unchanged !! Change to 33M 0x1B7C Priority 2 : 9375000 MPLS TE improves the efficiency of traffic spread across the network, avoiding inadequate and overuse of links. Ip cef tunnel interface can be configured directly IGP Metric , for example, if the running OSPF , directly in the tunnel configuration mouth ip ospf cost can MPLS is a forwarding technology based on packet labeling LSP Checksum The loopback0 address space of all devices is xxxx/32 , and x is the device number. Now let's add R4 . Note that R4 is only equipped with OSPF at this time . First, don't configure mpls ip on the interface connected to R1 (or use The distribution of the label is like this: Route metric is 168, traffic share count is 1 LDP discovery sources: The concept of "similar" in IP 75000 R1 , R2 , R3 , and R4 are in Transit AS 1234 . The IGP protocol running in the AS is OSPF. LSP overview Router(config)#ip explicit-path name ccietea Ip address 5.5.5.5 255.255.255.0 ip router isis Next, let's take a look at the details of these LSPs : Metric Type: TE (default) Mpls traffic-eng router-id loopback0 mpls traffic-eng area 0 Based on the platform ( of Per-Platform ) label space of just a LDPsession , even in the LDP there are multiple redundant links between neighbors 12 The configuration of R2 is as follows (all configurations are omitted from the configuration of interface IP ): Packet data unit data unit Network 10.1.23.2 0.0.0.0 area 0 *Aug 18 09:06:07.919: Tun Dest: 5.5.5.5 Tun ID: 0 Ext Tun ID: 1.1.1.1 ! Interface is up and sending maximum metric (Tunnel0) Destination: 4.4.4.4 All tag mapping messages received locally from the neighbor are saved in the database. 880 *Aug 18 04:37:06.239: Minimum Path Bandwidth (bytes/sec): 1250000 InLabel : - From which interface a tag packet is received, as long as it has this tag, it will be exchanged. ISO 9542 Labels 0-15 are all reserved labels. Here are some reserved tags that have a specific role: With PHP's penultimate hop pop-up mechanism, C allocates POP labels for local direct-connected prefixes and advertises them to other LDP neighbors. Network 10.1.23.3 0.0.0.0 area 0 Router-id 4.4.4.4 Ip address 10.1.12.1 255.255.255.0 Interface eth0/1 The router on Lan establishes adjacency with all other routers. In OSPF , the router on the LAN only establishes adjacency with the DR . LSP various types of TLV 3.3.3.0 [115/20] via 10.1.34.3, Serial0/0 The configuration of R1 is very critical, let's focus on it: LDP autoconfig Tunnel mpls traffic-eng path-option 10 explicit name R2R4R5 If a particular interface does not wish to activate LDP , use no mpls ldp igp to turn off LDP . The L1 router only has the link state database of Level1 in the area , and contains routing information of all L1 routers in the area. Mpls traffic-eng tunnels ip rsvp bandwidth Complete basic IP configuration (configuration omitted) *Aug 18 04:37:06.239: SENDER_TEMPLATE type 7 length 12: Type 7 length 16: Path: valid If a tunnel1 establish priority than the tunnel2 high hold priority, then tunnel1 be able to seize tunnel2 Ip address 5.5.5.5 255.255.255.255 Modify the bandwidth UP/DOWN threshold [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. 10.1.12.2 LSP , using LSP to carry all routing information The tail router of the TE tunnel receives this PATH message. The above command will directly change the cost of the above calculated route to y. Configure the requested bandwidth of the tunnel The interface of each router activates RSVP and MPLS TE tunnel support. 0 kbits/sec Bw[2]: Kbps (Global) Priority: 7 7 Affinity: 0x0/0xFFFF *Aug 18 09:06:07.919: 10.1.24.2 (Strict IPv4 Prefix, 8 bytes, /32) 10.1.13.3 This can be area at any level within the router adjacency relationship; may be other area adjacent L2 or L1 / L2 router forming L2 *Aug 18 09:06:07.919: Path MTU: 1500 10.1.12.2 Contains information such as the tunnel destination address, tunnel ID ,ccna online exam paper, and extended tunnel ID (that is, the tunnel start point) Interface eth0/1 The attribute used to describe the physical link consists of 32 bits . Each bit can represent an attribute of the link (such as whether it is encrypted or not) or a managed policy. There is no specific syntax for this 32bits . Each bit can be set to the latter without moving it. The network designer can think of specifying a specific meaning for a particular bit as needed . Fast tag rewrite with Fa0/0, 10.1.12.2, tags commit: {203} via 10.1.12.2, FastEthernet0/0, 0 dependencies Use the lockdown keyword (note that the above configuration is configured in the TE tunnel port). Show clns int Route-target export 2345:5 Ip rsvp bandwidth Ip route 5.5.5.5 255.255.255.255 Tunnel0 The PoP : receives downstream air sent by the tag assigned to a specific prefix, the value of this tag is 3 , then the LSR to the downstream LSR transmits the prefix data destined time, he will put up top label ( the POP ) for Forward, note that this time only need to check for this LSR Configure targeted-hello accept acl Interface Mpls traffic-eng tunnels mpls label range 200 299 Let's take a look at the routing table for R1 : *Aug 18 11:26:02.546: 0 kbits/sec Explicit Route: 10.1.12.2 10.1.23.2 10.1.23.3 10.1.34.3 Tunnel mpls traffic-eng fast-reroute The establishment of an OSPF adjacency involves a more complex process. LSPID Calculated. In the figure above, the red path is calculated by CSPF . 10.1.23.3 [MPLS: Label 300 Exp 0] 0 msec 0 msec 0 msec *Aug 18 11:26:02.546: 2.2.2.2 CSPF algorithm overview 4 10.1.45.5 8 msec 8 msec * ISO10589 R1#show ip cef 4.4.4.0 detail 4.4.4.0/24, epoch 0 i ia 5.5.5.0 [115/158] via 10.1.123.2, FastEthernet0/0 10.0.0.0/24 is subnetted, 4 subnets The configuration of R1 is as follows (other basic configurations are omitted directly): R1(config-if)#isis authentication key-chain test level-1 R1(config-if)#isis authentication mode md5 level-1 Negotiating Label space Mpls ldp sync 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 : And PSNP. 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 : Ip router isis router isis R2 is preferably a route from the tunnel port. At this time , the traffic from R2 to 55.55.55.55 is on the tunnel , and the LSP is used for label switching. Certification Information Ip unnumbered loopback 0 InLabel : - ! The global configuration command metric-style wide allows the cisco router to run the appropriate IOS version to send LSPs carrying the width. Router ospf 1 *Aug 18 09:06:07.919: 10.1.45.5 (Strict IPv4 Prefix, 8 bytes, /32) Type escape sequence to abort. Tracing the route to 4.4.4.4 My Address: 10.1.45.4 1.1.1.0 is directly connected, Loopback0 2.0.0.0/24 is subnetted, 1 subnets There are two types of tunnel priorities: Network 10.1.56.6 0.0.0.0 area 0 Remote binding: tsr: 2.2.2.2:0, tag: 200 Record Route: 10.1.23.2 10.1.34.3 10.1.45.4 10.1.45.5 The bandwidth information that MPLS TE needs to advertise is: 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. In the TE tunnel, a signaling protocol is needed to ensure that the link of the LSR interface traversed by the TE tunnel can be used and can be hop-by-hop. Bw[1]: InLabel : - Each IP packet forwarded to a router is the same before and after being forwarded through the router. 2.2.2.2/32 TE with Layer3 Ip cef Ip address 4.4.4.4 255.255.255.255 ERROR_SPEC MPLS TE configuration and experiment R1#show ip route 5.5.5.0 Bw[1]: Active Path Option Parameters: LSP ID (link status packet identifier) *Aug 18 09:06:02.699: 10.1.24.4 (Strict IPv4 Prefix, 8 bytes, /32) RFC 2210 The Use of RSVP with IETF Intergrated Services RFC3209 RSVP Extension to TE Interface Ethernet0/1 Link type supported by IS-IS Phenomenon and troubleshooting 75000 10.1.12.2 1.1.1.1 Interface Ip unnumbered Loopback0 tunnel mode mpls traffic-eng tunnel destination 5.5.5.5 Ip address 3.3.3.3 255.255.255.255 There are two types of tunnel priorities: TCP connection: 3.3.3.3.33664 - 1.1.1.1.646 *Aug 18 09:06:07.919: Error Code: 24 (Routing Problem) R1#show mpls traffic-eng tunnels ! Network 3.3.3.3 0.0.0.0 area 0 L1/L2 router re-releases external routes into IS-IS ( to level2 ) R1#show mpls traffic-eng tunnels protection Is-type level-1 Auto-bw: disabled Fa0/0 Uptime: 12 seconds 0xE7D9 Mpls traffic-eng tunnels ip rsvp bandwidth R1#traceroute 55.55.55.55 3.3.3.3/32 Interface Tunnel0 In TLV ), other messages were not seen. The command is as follows (interface level): Is-type level-1 Next Hop IS-IS and OSPF Area address Mpls traffic-eng tunnels ip rsvp bandwidth RESVErr is sent to the tail router Router ospf 1 *Aug 18 04:37:06.239: Tun Dest: 5.5.5.5 Tun ID: 0 Ext Tun ID: 1.1.1.1 Debug ip rsvp dump-messages R3#show ip route The global configuration command metric-style wide allows the cisco router to run the appropriate IOS version to send LSPs carrying the width. Ip cef !! Pay close attention to here 302 No mpls ip propagate-ttl [ forwarded | local ] Mpls traffic-eng tunnels mpls label range 100 199 1.0.0.0/32 is subnetted, 1 subnets Note that since R1 activates MPLS LDP-IGP synchronization, before the LDP adjacency relationship between R1 and R4 is established, the interface connecting R4 on R1 will not send OSPF HELLO packets, that is, R1-R4 . OSPF adjacencies can never be established. Of course, we don't want to watch the R1-R4 screw up, it's not good for anyone, isn't it? So configure one on R1 : CSNP The link ID can be the router ID of the neighbor . If it is a multiple access link, it is the interface address of the DR . Do not need to explain it again? At R4 , R4 pops the top label and forwards the packet to R5. The labels constituting the LFIB may not be distributed by LDP , and the RSVP allocation label is used in the MPLS traffic engineering . In the MPLS VPN , Global Pool Sub Pool O 10.1.23.0 [110/2] via 10.1.12.2, 00:00:37, FastEthernet0/0 Replaces both IP Reachability TLVs ( 128 and 130 ) . Uses wide metrics Router isis *Aug 18 09:06:07.919: SENDER_TEMPLATE type 7 length 12: Mpls ip interface fa1/0 L1 / L2router with the set attached-bit route-map associated with a route-map test deny the route-Map , it. R3.00-00 Configure this hidden command on the penultimate hop router (that is, R2 in the figure above ): R1(config-keychain-key)#key-string cisco R1(config-keychain-key)#exit Tracing the route to 55.55.55.55 1.1.1.1/32 Mpls ldp igp sync holddown msecs R2#show ip route FastEthernet1 / 0, Src IP addr: 10.1.13.3 Addresses bound to peer LDP Ident: ----------- Downstream assigned label Policy routing Mpls traffic-eng tunnels ip rsvp bandwidth Both R3 and R5 must activate the forwarding adjacency feature. Test . 3 : SET-overload 'bit-ON-120 Startup Prefix *Aug 18 09:06:02.699: SENDER_TSPEC type 2 length 36: Tunnel priority Do not elect DIS , use CSNP to trigger database synchronization after the link is established . The affinity attribute is a property that describes the MPLS TE tunnel and is also composed of 32 bits , which is exactly the same as the number of attribute-flags mentioned above . Also configured with the affinity attribute is a mask, also 32bits , which is used to match the attribute tag and the affinity attribute.