ccna routing and switching questions and answers

ccna routing and switching questions and answers

Describes all LSP information in the LSP database . Router-id 2.2.2.2 Source routing, policy routing, static routing, etc. Name: R2-PE1_t0 Status: PSNP Swap Therefore, when R2 sends the label packet to the tunnel , the label that is pushed into the outer layer is 304 , and this 304 is obviously allocated by R3 , and is the label assigned by RSVP to the TE tunnel . Set-attached-bit route-map test RSVP Basically, the LSP is the path through the MPLS network or a part of it that packets take. // One-way path. In fact, an LSP is a path when a packet traverses an MPLS network or a part of an MPLS network. Cisco Press - IS-IS Network Design Solutions IS-IS Network Design Solutions 0x2995 Network 10.1.12.1 0.0.0.0 area 0 *Aug 18 04:37:06.239: HOP type 1 length 12: Swap: The top label is removed and a new label is used instead of the removed label. OSPF 's DR *Aug 18 11:26:02.546: Interface Tunnel0 LSRs maintain only one LDPsession for each label space Mpls traffic-eng tunnels ip rsvp bandwidth After the feature is activated, both R3 and R5 advertise the existence of this tunnel (in the form of a direct link) within the zone . Equivalent to having one more path (virtual path) in the topology environment. !! The type of IS is level1 Support IP classless routing prefix (support VLSM ) information information Local binding: tag: imp-null R1#show mpls traffic-eng tunnels Mpls ip Ip rsvp bandwidth Virtual link *Aug 18 11:31:44.598: 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 . State Verify that you receive the LDP Hello from the other party. The default on the point to point link 10S sent once IIH . Extended OSPF and IS-IS to TE required information flooding in the network, then Tunnel head-end router can build your own TE Admin: up ! Downstream active mode : Downstream Unsolicited Peer LDP Ident: 2.2.2.2:0; Local LDP Ident 1.1.1.1:0 ----------- ---------- L1 (inside the area) and L2 (in the area) Redistribute isis ip level-2 into level-1 route-map test Mpls label rangempls label range 300 399 interface fa0/0 ISO10589 * 0x0000002B i L1 Fa0/0 If the MPLS payload is an IPv4 or IPv6 packet, CISCO IOS is used in a destination-based load balancing environment. Router ospf 100 LSP Tunnel R1_t0 is signalled, connection is up Status Minimum Path Bandwidth (bytes/sec): 2147483647 Path Latency (microseconds): 0 information IS-IS interface. If the interface is attached to a multiaccess network, the circuit ID is concatenated with the system ID of the DIS ” Interface eth0/0 *Aug 18 09:06:07.919: Controlled Load Service break bit=0 service length=0 The routing table of R3 is as follows (omit direct route): Regional separation Fa0/0 The TLVs used are: The configuration of R5 is as follows: If the link or node fails, the traffic will be rerouted due to the failure. If the rerouting takes a few seconds, the high performance of the link will cause a large amount of traffic pointing to the fault point to be discarded. For some businesses, business interruption may result. Ip address 5.5.5.5 255.255.255.255 The overload feature is, after all, a product of an era in which device performance is not strong enough. However , the extended application of overload is very worthy of attention. Let's take a look at the following picture: Prefix adjacent router 5.5.5.5 Tun ID: 0 Ext Tun ID: 1.1.1.1 Next Hop Comparison of terms between IS-IS and OSPF : Tunnel priority (Tunnel0) Destination: 5.5.5.5 Tspec: ave rate=0 kbits, burst=1000 bytes, peak rate=0 kbits RSVP Resv Info: Record Route: 2.2.2.2(200) 4.4.4.4(403) *Aug 18 11:31:44.598: Once LDP is activated, the LSR generates a label locally for the prefix in the routing table, and then bundles it with the prefix to send the label mapping message to all LDP neighbors. When I receive the remote binding from the LDP neighbor , I bundle the tags and the local bindings that are localized for the specific prefix into the LIB . Mpls traffic-eng router-id loopback 0 mpls traffic-eng level-1 Select the path with the least number of hops Mpls traffic-eng tunnels mpls label range 400 499 Address-family vpnv4 neighbor 2.2.2.2 activate *Aug 18 09:06:02.699: Refresh Period (msec): 30000 Mpls traffic-eng router-id loopback0 mpls traffic-eng area 0 0x8000001A 0x002ED2 0 MPLS label header. At the same time, the header of the Layer 2 data link layer will be instructed accordingly. For example, the Ethernet data frame,ccna routing and switching questions and answers, the TYPE field of the MAC layer indicates whether the upper layer data is an mpls label frame (if it is an IPv4 packet, the value is 0x0800 , if it is a label packet) Then it is 8847 -unicast or 8848- multicast) *Aug 18 11:31:44.598: Router ospf 1 In the Level1 link state database. Each zone in the IS-IS domain has a unique Level1 link state database. The shortest path is calculated by the SPF algorithm. 33000 Type Block 42000 *Aug 18 11:26:02.546: RFC1195 Ip router isis router isis L2 router Needless to say this? At this time, TTL propagation can be turned off ( CISCO router is enabled by default) Network 1.1.1.1 0.0.0.0 area 0 Router ospf 1 vrf VPN-A redistribute bgp 2345 subnets network 10.1.12.2 0.0.0.0 area 0 0/0/0 ! InLabel : - The main function of the ES-IS protocol is to provide mapping of NSAP addresses to SNPA addresses for network devices . Ip address 10.1.255.1 255.255.255.255 Tunnel mpls traffic-eng autoroute announce Next-address loose 10.1.45.5 Tunnel destination 4.4.4.4 tunnel mode mpls traffic-eng Local binding: tag: 101 Mpls traffic-eng tunnels mpls ip The configuration of R5 is supplemented as follows: 102 Protocols support Next-address 10.1.23.3 R1#show mpls traffic-eng tunnels LS age: 29 InLabel : - R1 is based on the remaining two paths, then compare TE metric (default is equal to IGP Metric ) LSP Seq Num LSP Checksum LSP Holdtime Device Although R5 and R6 can learn each other's routes, they cannot communicate with each other because routing black holes appear on R2 and R3 . The solution is to use MPLS , we turn the Core into an MPLS domain: Requirements for IGP Show mpls traffic-eng link-management advertisement Achieve reliability No frame-relay inverse-arp Three-way handshake mechanism: 75000 Environmental description The forwarding adjacency feature will cause the TE router to advertise the TE tunnel as a virtual path (direct link) in the IGP routing protocol area, so that all routers know the existence of the tunnel. The IGP protocol here can be OSPF or IS-IS. The configuration of R3 is as follows: [110/3] via 10.1.23.2, 00:53:36, FastEthernet0/0 2.2.2.2 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. Route-target import 2345:5 The loopback0 address space of all devices is xxxx/32 , and x is the device number. bibliography L2 router has a Level 2 link state database, which contains routing information between all areas. Supports allocating network resources for explicit LSP tunnels Ip address 4.4.4.4 255.255.255.255 Tunnel mpls traffic-eng path-option 10 dynamic Prefix Look again at R4 's isis database : Router ospf 1 ! Peer LDP Ident: 2.2.2.2:0; Local LDP Ident 1.1.1.1:0 TCP connection: 2.2.2.2.31044 - 1.1.1.1.646 Next, let's look at the isis database of R1 : 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. See below for more details on how labels are handled. ! Physical Bandwidth: Physical bandwidth of the 100000 kbits/sec !! interface Basic experiment 1 !! Backup tunnel This configuration is suitable for situations with explicit session endpoints. The configuration of R5 is as follows: Ip address 10.1.255.1 255.255.255.255 OSPF divides areas based on interfaces. Routers can belong to different areas. (Link ID) Designated Router address: 10.1.23.3 (Link Data) Router Interface address: 10.1.23.2 Number of MTID metrics: 0 Mpls traffic-eng tunnels ip rsvp bandwidth i ia 5.5.5.0 [115/158] via 10.1.123.2, FastEthernet0/0 10.0.0.0/24 is subnetted, 4 subnets *Aug 18 09:06:02.699: Path MTU: 1500 Used to uniquely identify an LSP and authentication source router 131 Route-target export 2345:5 75000 *Aug 18 09:06:07.919: Inter-domain routing protocol Interface fa0/0 During the ES-IS work process, the end system sends an ESH ( ES Hello ) message to a specific address to notify the router of its existence. The router listens to the ESH packet to discover the ES existing in the network , so that the packet arriving at the specific ES address is subsequently forwarded to the ES . In ES-IS , the router advertises its own existence to the ES by sending an ISH ( IS Hello ) message to a specific address . ES also monitor ISH , if a plurality of received IS transmitted ISH , ES will then be selected, and sends all data to the IS .