As shown in Figure 1, IS-IS is run on LSR A, LSR B, LSR C, and LSR D. They are all Level 2 devices.

RSVP-TE is used to establish a TE tunnel from LSR A to LSR D. The bandwidth is 20 Mbit/s. The maximum reservable bandwidth of links along the tunnel is 100 Mbit/s. The bandwidth constraints model is the default RDM and the bandwidth of BC0 is 100 Mbit/s.

Figure 1 Networking diagram of the RSVP-TE tunnel

Configuration Roadmap

The configuration roadmap is as follows:

1. Configure IP addresses for the interfaces on each LSR and configuring loopback address as the LSR ID.
2. Enable IS-IS globally, configure the name of network entity, change cost type, enable IS-IS TE and enable IS-IS on all interfaces including loopback interfaces.
3. Configure LSR ID and enable MPLS, MPLS TE, MPLS RSVP-TE, and MPLS TE CSPF globally.
4. Enable MPLS, MPLS TE, and MPLS RSVP-TE on each interface.
5. Configure the maximum reservable bandwidth and BC bandwidth for the links on each LSR along the tunnel.
6. Create the tunnel interface on the ingress and specifying the IP address, tunnel protocol, destination address, tunnel ID, dynamic signaling protocol RSVP-TE, and tunnel bandwidth.

Data Preparation

To complete the configuration, you need the following data:

• IS-IS area ID of each LSR, originating system ID, and IS-IS level
• Maximum reservable bandwidth and BC bandwidth for the links along the tunnel
• Tunnel interface name, IP address, destination address, tunnel ID, tunnel signaling protocol (RSVP-TE), and tunnel bandwidth

Configuration Procedure

1. Configure IP addresses for interfaces.Configure the IP address and mask on each interface as shown in Figure 1. The detailed configuration is not mentioned here.
2. Configure the IS-IS protocol to advertise routes.# Configure LSR A.

   [LSRA] isis 1

   [LSRA-isis-1] network-entity 00.0005.0000.0000.0001.00

   [LSRA-isis-1] is-level level-2

   [LSRA-isis-1] quit

   [LSRA] interface gigabitethernet 1/0/0

   [LSRA-GigabitEthernet1/0/0] isis enable 1

   [LSRA-GigabitEthernet1/0/0] quit

   [LSRA] interface loopback 1

   [LSRA-LoopBack1] isis enable 1

   [LSRA-LoopBack1] quit

   # Configure LSR B.

   [LSRB] isis 1

   [LSRB-isis-1] network-entity 00.0005.0000.0000.0002.00

   [LSRB-isis-1] is-level level-2

   [LSRB-isis-1] quit

   [LSRB] interface gigabitethernet 1/0/0

   [LSRB-GigabitEthernet1/0/0] isis enable 1

   [LSRB-GigabitEthernet1/0/0] quit

   [LSRB] interface pos 2/0/0

   [LSRB-Pos2/0/0] isis enable 1

   [LSRB-Pos2/0/0] quit

   [LSRB] interface loopback 1

   [LSRB-LoopBack1] isis enable 1

   [LSRB-LoopBack1] quit

   # Configure LSR C.

   [LSRC] isis 1

   [LSRC-isis-1] network-entity 00.0005.0000.0000.0003.00

   [LSRC-isis-1] is-level level-2

   [LSRC-isis-1] quit

   [LSRC] interface gigabitethernet 1/0/0

   [LSRC-GigabitEthernet1/0/0] isis enable 1

   [LSRC-GigabitEthernet1/0/0] quit

   [LSRC] interface pos 2/0/0

   [LSRC-Pos2/0/0] isis enable 1

   [LSRC-Pos2/0/0] quit

   [LSRC] interface loopback 1

   [LSRC-LoopBack1] isis enable 1

   [LSRC-LoopBack1] quit

   # Configure LSR D.

   [LSRD] isis 1

   [LSRD-isis-1] network-entity 00.0005.0000.0000.0004.00

   [LSRD-isis-1] is-level level-2

   [LSRD-isis-1] quit

   [LSRD] interface gigabitethernet 1/0/0

   [LSRD-GigabitEthernet1/0/0] isis enable 1

   [LSRD-GigabitEthernet1/0/0] quit

   [LSRD] interface loopback 1

   [LSRD-LoopBack1] isis enable 1

   [LSRD-LoopBack1] quit

   After the configuration, run the display ip routing-table command on each LSR, and you can view that LSRs learned routes from each other.

   Take the display on LSR A as an example.

   [LSRA] display ip routing-table

   Route Flags: R - relay, D - download to fib
   ------------------------------------------------------------------------------
   Routing Tables: Public

            Destinations : 10       Routes : 10
   

   Destination/Mask  Proto  Pre  Cost   Flags  NextHop         Interface
   

         1.1.1.9/32  Direct 0    0          D  127.0.0.1       InLoopBack0

         2.2.2.9/32  ISIS   15   10         D  10.1.1.2        GigabitEthernet1/0/0

         3.3.3.9/32  ISIS   15   20         D  10.1.1.2        GigabitEthernet1/0/0

         4.4.4.9/32  ISIS   15   30         D  10.1.1.2        GigabitEthernet1/0/0

        10.1.1.0/24  Direct 0    0          D  10.1.1.1        GigabitEthernet1/0/0

        10.1.1.1/32  Direct 0    0          D  127.0.0.1       InLoopBack0

        20.1.1.0/24  ISIS   15   20         D  10.1.1.2        GigabitEthernet1/0/0

        30.1.1.0/24  ISIS   15   30         D  10.1.1.2        GigabitEthernet1/0/0

       127.0.0.0/8   Direct 0    0          D  127.0.0.1       InLoopBack0

       127.0.0.1/32  Direct 0    0          D  127.0.0.1       InLoopBack0

3. Configure the basic MPLS functions and enable MPLS TE, RSVP-TE, and CSPF.# Enable MPLS, MPLS TE, and RSVP-TE globally on each LSR, enable MPLS, MPLS TE, and RSVP-TE on all tunnel interfaces, and enable CSPF in the system view on the ingress.# Configure LSR A.

   [LSRA] mpls lsr-id 1.1.1.9

   [LSRA] mpls

   [LSRA-mpls] mpls te

   [LSRA-mpls] mpls rsvp-te

   [LSRA-mpls] mpls te cspf

   [LSRA-mpls] quit

   [LSRA] interface gigabitethernet 1/0/0

   [LSRA-GigabitEthernet1/0/0] mpls

   [LSRA-GigabitEthernet1/0/0] mpls te

   [LSRA-GigabitEthernet1/0/0] mpls rsvp-te

   [LSRA-GigabitEthernet1/0/0] quit

   # Configure LSR B.

   [LSRB] mpls lsr-id 2.2.2.9

   [LSRB] mpls

   [LSRB-mpls] mpls te

   [LSRB-mpls] mpls rsvp-te

   [LSRB-mpls] quit

   [LSRB] interface gigabitethernet 1/0/0

   [LSRB-GigabitEthernet1/0/0] mpls

   [LSRB-GigabitEthernet1/0/0] mpls te

   [LSRB-GigabitEthernet1/0/0] mpls rsvp-te

   [LSRB-GigabitEthernet1/0/0] quit

   [LSRB] interface pos 2/0/0

   [LSRB-Pos2/0/0] mpls

   [LSRB-Pos2/0/0] mpls te

   [LSRB-Pos2/0/0] mpls rsvp-te

   [LSRB-Pos2/0/0] quit

   # Configure LSR C.

   [LSRC] mpls lsr-id 3.3.3.9

   [LSRC] mpls

   [LSRC-mpls] mpls te

   [LSRC-mpls] mpls rsvp-te

   [LSRC-mpls] quit

   [LSRC] interface gigabitethernet 1/0/0

   [LSRC-GigabitEthernet1/0/0] mpls

   [LSRC-GigabitEthernet1/0/0] mpls te

   [LSRC-GigabitEthernet1/0/0] mpls rsvp-te

   [LSRC-GigabitEthernet1/0/0] quit

   [LSRC] interface pos 2/0/0

   [LSRC-Pos2/0/0] mpls

   [LSRC-Pos2/0/0] mpls te

   [LSRC-Pos2/0/0] mpls rsvp-te

   [LSRC-Pos2/0/0] quit

   # Configure LSR D.

   [LSRD] mpls lsr-id 4.4.4.9

   [LSRD] mpls

   [LSRD-mpls] mpls te

   [LSRD-mpls] mpls rsvp-te

   [LSRD-mpls] quit

   [LSRD] interface gigabitethernet 1/0/0

   [LSRD-GigabitEthernet1/0/0] mpls

   [LSRD-GigabitEthernet1/0/0] mpls te

   [LSRD-GigabitEthernet1/0/0] mpls rsvp-te

   [LSRD-GigabitEthernet1/0/0] quit

4. Configure IS-IS TE.# Configure LSR A.

   [LSRA] isis 1

   [LSRA-isis-1] cost-style wide

   [LSRA-isis-1] traffic-eng level-2

   [LSRA-isis-1] quit

   # Configure LSR B.

   [LSRB] isis 1

   [LSRB-isis-1] cost-style wide

   [LSRB-isis-1] traffic-eng level-2

   [LSRB-isis-1] quit

   # Configure LSR C.

   [LSRC] isis 1

   [LSRC-isis-1] cost-style wide

   [LSRC-isis-1] traffic-eng level-2

   [LSRC-isis-1] quit

   # Configure LSR D.

   [LSRD] isis 1

   [LSRD-isis-1] cost-style wide

   [LSRD-isis-1] traffic-eng level-2

   [LSRD-isis-1] quit

5. Configure the MPLS TE link bandwidth.# Configure the maximum reservable bandwidth and the maximum BC0 bandwidth of the link on all tunnel interfaces.# Configure LSR A.

   [LSRA] interface gigabitethernet 1/0/0

   [LSRA-GigabitEthernet1/0/0] mpls te bandwidth max-reservable-bandwidth 100000

   [LSRA-GigabitEthernet1/0/0] mpls te bandwidth bc0 100000

   [LSRA-GigabitEthernet1/0/0] quit

   # Configure LSR B.

   [LSRB] interface pos2/0/0

   [LSRB-Pos2/0/0] mpls te bandwidth max-reservable-bandwidth 100000

   [LSRB-Pos2/0/0] mpls te bandwidth bc0 100000

   [LSRB-Pos2/0/0] quit

   # Configure LSR C.

   [LSRC] interface gigabitethernet 1/0/0

   [LSRC-GigabitEthernet1/0/0] mpls te bandwidth max-reservable-bandwidth 100000

   [LSRC-GigabitEthernet1/0/0] mpls te bandwidth bc0 100000

   [LSRC-GigabitEthernet1/0/0] quit

6. Configure MPLS TE tunnel interface.# Create tunnel interfaces on the ingress. Then configure IP addresses for the tunnel interfaces, tunnel protocol, destination address, tunnel ID, dynamic signaling protocol, and tunnel bandwidth. Finally, commit the configurations to validate them by using the mpls te commit command.# Configure LSR A.

   [LSRA] interface tunnel 1/0/0

   [LSRA-Tunnel1/0/0] ip address unnumbered interface loopback 1

   [LSRA-Tunnel1/0/0] tunnel-protocol mpls te

   [LSRA-Tunnel1/0/0] destination 4.4.4.9

   [LSRA-Tunnel1/0/0] mpls te tunnel-id 100

   [LSRA-Tunnel1/0/0] mpls te signal-protocol rsvp-te

   [LSRA-Tunnel1/0/0] mpls te bandwidth ct0 20000

   [LSRA-Tunnel1/0/0] mpls te commit

   [LSRA-Tunnel1/0/0] quit

7. Verify the configuration.After the configuration, run the display interface tunnel command on LSR A, and you can view that the status of the tunnel interface goes Up.

   [LSRA] display interface tunnel

   Tunnel1/0/0 current state : UP

   Line protocol current state : UP

   Last up time: 2009-01-15, 16:35:10

   Description : Tunnel1/0/0Interface

   Route Port,The Maximum Transmit Unit is 1500 bytes

   Internet Address is unnumbered, using address of LoopBack1(1.1.1.9/32)

   Encapsulation is TUNNEL, loopback not set

   Tunnel destination 4.4.4.9

   Tunnel up/down statistics 1

   Tunnel protocol/transport MPLS/MPLS, ILM is available,

   primary tunnel id is 0x1002001, secondary tunnel id is 0x0

       300 seconds output rate 0 bits/sec, 0 packets/sec

       22 seconds output rate 0 bits/sec, 0 packets/sec

       0 packets output,  0 bits

       0 output error

       ct0:0 packets output,  0 bytes
           0 output error

   Run the display mpls te tunnel-interface command on LSR A to display the information on the tunnel.

   [LSRA] display mpls te tunnel-interface tunnel1/0/0

       Tunnel Name       :  Tunnel1/0/0
       Tunnel State Desc :  CR-LSP is Up
       Tunnel Attributes   :
       Session ID          :  100
       Ingress LSR ID      :  1.1.1.9               Egress LSR ID:  4.4.4.9
       Admin State         :  UP                    Oper State   :  UP
       Signaling Protocol  :  RSVP
       Tie-Breaking Policy :  None                  Metric Type  :  None
       Car Policy          :  Disabled              Bfd Cap      :  None
       BypassBW Flag       :  Not Supported
       BypassBW Type       :  -                     Bypass BW    :  -
       Retry Limit         :  5                     Retry Int    :  2 sec
       Reopt               :  Disabled              Reopt Freq   :  -
       Auto BW             :  Disabled
       Current Collected BW:  -                     Auto BW Freq :  -
       Min BW              :  -                     Max BW       :  -
       Tunnel  Group       :  Primary
       Interfaces Protected:  -
       Excluded IP Address :  -
       Is On Radix-Tree    :  Yes                   Referred LSP Count:  0
       Primary Tunnel      :  -                     Pri Tunn Sum :  -
       Backup Tunnel       :  -
       Group Status        :  Up                    Oam Status   :  Up
       IPTN InLabel        :  -
       BackUp Type         :  None                  BestEffort   :  Disabled
       Secondary HopLimit  :  -
       BestEffort HopLimit :  -
       Secondary Explicit Path Name:  -
       Secondary Affinity Prop/Mask:  0x0/0x0
       BestEffort Affinity Prop/Mask:  0x0/0x0
   
       Primary LSP ID      :  1.1.1.9:1
       Setup Priority      :  7                     Hold Priority:  7
       Affinity Prop/Mask  :  0x0/0x0               Resv Style   :  SE
       CT0 Reserved BW(Kbit/sec): 20000        CT1 Reserved BW(Kbit/sec): 0
       CT2 Reserved BW(Kbit/sec): 0            CT3 Reserved BW(Kbit/sec): 0
       CT4 Reserved BW(Kbit/sec): 0            CT5 Reserved BW(Kbit/sec): 0
       CT6 Reserved BW(Kbit/sec): 0            CT7 Reserved BW(Kbit/sec): 0
       Actual Bandwidth(kbps):  20000
       Explicit Path Name  :  -                     Hop Limit    :  -
       Record Route        :  Disabled              Record Label :  Disabled
       Route Pinning       :  Disabled
       FRR Flag            :  -
       IdleTime Remain     :  -
   

   Run the display mpls te cspf tedb all command on LSR A to display the link information in the TEDB.

   [LSRA] display mpls te cspf tedb all

   Maximum Node Supported: 128              Maximum Link Supported: 256

   Current Total Node Number: 4             Current Total Link Number: 6

   Id     Router-Id     IGP      Process-Id   Area         Link-Count

   1      3.3.3.9       ISIS     1            Level-2       2

   2      2.2.2.9       ISIS     1            Level-2       2

   3      4.4.4.9       ISIS     1            Level-2       1

   4      1.1.1.9       ISIS     1            Level-2       1