ccna basic questions

ccna basic questions

Interface Tunnel0 That is the CEF table Generate a default route to this device as the egress route by ATT bit with its nearest L1/L2 router Interface eth0 1/0 Ciphertext interface authentication ATT/P/OL *Aug 18 09:06:07.919: Refresh Period (msec): 30000 8 Bandwidth information Activate the MPLS TE tunnel feature on the interface. State: Oper; Msgs sent/rcvd: 13/13; Downstream Up time: 00:03:47 System Id Type Interface IP Address State Holdtime Circuit Id Ip rsvp bandwidth SystemID : The systemID of the IS that generated the hello (some books have a SourceID , synonymous) MPLS coding !! Specify the range of local tags,ccna basic questions, this can be a great convenience in the experiment R5 is also similar: 0x2F89 LDP inbound label binding filter Interface eth0/0 Router(config-router)#mpls traffic-eng area x Run OSPF on the entire network to announce direct connection and loopback interface. R2-PE1#show ip route [0]: (Tunnel0) Destination: 4.4.4.4 Interface fast 0/0 Tunnel priority Tib entry: 1.1.1.1/32, rev 2 the term The router uses a local circuit ID of 8 bits to assign a local unique link identifier to each point-to-point link. basic configuration 128 Therefore, we activate the forwarding adjacency feature on the CISCO IOS router, except that the TE tunnel endpoint router advertises the tunnel as a direct link, and also considers the tunnel when it performs the SPF algorithm calculation . And if we modify the IGP of the tunnel port *Aug 18 11:26:02.546: Is a group or flow of packets that are forwarded along the same path and are treated the same with regard to the forwarding treatment. After flooding related information through the IGP protocol ( OSPF or ISIS ), all TE routers form a unified TEDB in the area. Intermediate System to Intermediate System (IS-IS) Cryptographic Authentication Router(config)# mpls ldp targeted-hello holdtime x interval y Types of basic concept lab environment 10.1.23.2 Interface eth 0/1 *Aug 18 09:06:07.919: Tun Dest: 5.5.5.5 Tun ID: 0 Ext Tun ID: 1.1.1.1 Tunnel mode mpls traffic-eng tunnel destination 5.5.5.5 Mpls traffic-eng router-id loopback 0 mpls traffic-eng level-1 Network 10.1.34.4 0.0.0.0 area 0 Now we can try to modify the TE tunnel configuration of R1 : Mpls traffic-eng tunnels ip rsvp bandwidth ISO10589 You see that we have IS-IS metrics in many places in the LSP , for example: RFC 3784 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 . So now, we will change the loopback port address of R2 to 2.2.2.2/24 and change it to /24 to see what happens. Although the implicit null tag also uses a tag with a tag value of 3 , tag 3 will never appear in the tag stack of the MPLS message, which is why it is called an implicit null tag. Interface eth 0/1 TIME_VALUES 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, 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) Ip address 3.3.3.3 255.255.255.255 *Aug 18 04:37:06.239: Incoming PathError: !!R2 sends a patherror message to R1 RSVP message type Look at the LDP neighbor on R2 : Basic configuration It should be noted here that if a label package is received and the label is 0 , the label will be directly popped up and the data will be submitted to the FIB for searching, and there will be no loss of the search. Label tag with tag 0 , why not just remove the tag (allocate a 13 value to the next hop to let the next hop remove the tag), why keep the tag header with 0 ? This is to maintain the uniformity of network planning under certain circumstances. For example , if QoS of MPLS is deployed , the EXP field in the label package is required, and then a label is required. When QoS is implemented , the last hop must carry the exp bit. Therefore, the label cannot be ejected. You need to configure mpls ldp explicit-null. The label assigned to a specific route is 0 and passed to the LDP neighbor (such as the penultimate hop). .