Step 3: Examine the Traffic Engineering Database

Purpose

Examining the traffic engineering database is another way to locate the node that should meet the constraints but does not. Once identified, you can concentrate your troubleshooting efforts on why that node is not being represented accurately in the database.

The contents of the traffic engineering database are consistent among all routers within a given traffic engineering domain. Therefore, you can issue the show ted database command from any router in the same traffic engineering domain to obtain more granular information about the CSPF failure.

CSPF integrates topology link-state information that is learned from the IGP traffic engineering extensions and maintained in the traffic engineering database. The information stored in the traffic engineering database includes attributes associated with the state of the network resources (such as total link bandwidth, reserved link bandwidth, available link bandwidth, and link color). When calculating a path, the CSPF algorithm factors in user-provided information such as bandwidth requirements, maximum allowed hop count, and administrative groups, all of which are obtained from user configuration. (See Figure 5).

Figure 5: User-Provided Constraints

Action

To examine the traffic engineering database, enter the following JUNOS CLI operational mode commands:

user@host> show ted database extensive

user@host> show ted database extensive NodeID | match "(NodeID|To:|Color)" 

Sample Output 1

[edit protocols mpls]

user@R1# run show ted database extensive

TED database: 6 ISIS nodes 6 INET nodes

[...Output truncated...]

NodeID: R5.00(10.0.0.5)

  Type: Rtr, Age: 103 secs, LinkIn: 3, LinkOut: 3

  Protocol: IS-IS(2)

    To: R1.00(10.0.0.1), Local: 10.1.15.2, Remote: 10.1.15.1

      Color: 0x100 red

      Metric: 10

      Static BW: 155.52Mbps

      Reservable BW: 155.52Mbps

      Available BW [priority] bps:

          [0] 155.52Mbps   [1] 155.52Mbps  [2] 155.52Mbps  [3] 155.52Mbps  

          [4] 155.52Mbps   [5] 155.52Mbps  [6] 155.52Mbps  [7] 155.52Mbps  

      Interface Switching Capability Descriptor(1):

        Switching type: Packet

        Encoding type: Packet

        Maximum LSP BW [priority] bps:

          [0] 155.52Mbps   [1] 155.52Mbps  [2] 155.52Mbps  [3] 155.52Mbps  

          [4] 155.52Mbps   [5] 155.52Mbps  [6] 155.52Mbps  [7] 155.52Mbps  

    To: R4.00(10.0.0.4), Local: 10.1.45.2, Remote: 10.1.45.1

      Color: 0 <none>

      Metric: 10

      Static BW: 155.52Mbps

      Reservable BW: 155.52Mbps

      Available BW [priority] bps:

          [0] 155.52Mbps   [1] 155.52Mbps  [2] 155.52Mbps  [3] 155.52Mbps  

          [4] 155.52Mbps   [5] 155.52Mbps  [6] 155.52Mbps  [7] 155.52Mbps  

      Interface Switching Capability Descriptor(1):

        Switching type: Packet

        Encoding type: Packet

        Maximum LSP BW [priority] bps:

          [0] 155.52Mbps   [1] 155.52Mbps  [2] 155.52Mbps  [3] 155.52Mbps  

          [4] 155.52Mbps   [5] 155.52Mbps  [6] 155.52Mbps  [7] 155.52Mbps  

    To: R6.00(10.0.0.6), Local: 10.1.56.1, Remote: 10.1.56.2

      Color: 0 <none>

      Metric: 10

      Static BW: 155.52Mbps

      Reservable BW: 155.52Mbps

      Available BW [priority] bps:

          [0] 155.52Mbps   [1] 155.52Mbps  [2] 155.52Mbps  [3] 155.52Mbps  

          [4] 155.52Mbps   [5] 155.52Mbps  [6] 155.52Mbps  [7] 155.52Mbps  

      Interface Switching Capability Descriptor(1):

        Switching type: Packet

        Encoding type: Packet

        Maximum LSP BW [priority] bps:

          [0] 155.52Mbps   [1] 155.52Mbps  [2] 155.52Mbps  [3] 155.52Mbps  

          [4] 155.52Mbps   [5] 155.52Mbps  [6] 155.52Mbps  [7] 155.52Mbps 

[...Output truncated...]

Sample Output 2

[edit protocols]

user@R1# run show ted database extensive R5.00 | match "(NodeID|To:|Color)" 

NodeID: R5.00(10.0.0.5)

    To: R1.00(10.0.0.1), Local: 10.1.15.2, Remote: 10.1.15.1

      Color: 0x100 red

    To: R4.00(10.0.0.4), Local: 10.1.45.2, Remote: 10.1.45.1

      Color: 0 <none>

    To: R6.00(10.0.0.6), Local: 10.1.56.1, Remote: 10.1.56.2

      Color: 0 <none>

    To: R1.00(10.0.0.1), Local: 10.1.15.2, Remote: 10.1.15.1

      Color: 0x100 red

    To: R4.00(10.0.0.4), Local: 10.1.45.2, Remote: 10.1.45.1

      Color: 0 <none>

    To: R6.00(10.0.0.6), Local: 10.1.56.1, Remote: 10.1.56.2

      Color: 0 <none>

What It Means

Sample Output 1 from ingress router R1 shows a wealth of information on each node in the network, although only a portion is included in this example. The output shows the total number of IS-IS and INET nodes in the traffic engineering domain. The portion of the traffic engineering database shown represents a node (R5), and the Type field indicates Rtr (router). The Type field could also indicate Net (network) if the node were a pseudo node. The node (R5) has three input and output links that are running IS-IS Level 2, Protocol: IS-IS(2). The links lead to nodes R1, R4, and R6. The local address and remote address for each link is specified. The information on each node includes administrative groups (Color:), metrics, static bandwidth, reservable bandwidth, and available bandwidth priority level. The information contained in the traffic engineering database should be the same across all routers in the same traffic engineering domain. For a detailed description of the fields in the output of the show ted database extensive command, see the JUNOS Routing Protocols and Policies Command Reference.

Sample Output 2 shows filtered output that allows you to focus on exactly what is missing or incorrect.

Both outputs confirm that the link between R1 and R5, 10.1.15.0/32, is associated with the red color, while the link between R5 and R6, 10.1.56.0/32, is not associated with a color. In the network shown in Figure 4, for the LSP to establish correctly, link 10.1.56.1 must be associated with the red color.