Examining the History Log

Purpose

The history log for the show mpls lsp extensive command contains information that is useful in determining a possible reason for any errors in MPLS functioning in your network.

Action

To examine the history log, enter the following JUNOS CLI operational mode command:

user@host> show mpls lsp extensive

Sample Output

user@R6> show mpls lsp extensive

Ingress LSP: 1 sessions

10.0.0.1

From: 10.0.0.6, State: Up, ActiveRoute: 1, LSPname: R6-to-R1

  ActivePath:  (primary)

  LoadBalance: Random

  Encoding type: Packet, Switching type: Packet, GPID: IPv4

 *Primary                    State: Up

    Computed ERO (S [L] denotes strict [loose] hops): (CSPF metric: 20)

 10.1.56.1 S 10.1.15.1 S 

    Received RRO (ProtectionFlag 1=Available 2=InUse 4=B/W 8=Node 
10=SoftPreempt):

          10.1.56.1 10.1.15.1

    6 Aug 17 12:19:04 Selected as active path

    5 Aug 17 12:19:03 Record Route:  10.1.56.1 10.1.15.1

    4 Aug 17 12:19:03 Up

    3 Aug 17 12:19:03 Originate Call

    2 Aug 17 12:19:03 CSPF: computation result accepted

    1 Aug 17 12:18:34 CSPF failed: no route toward 10.0.0.1

  Created: Tue Aug 17 12:18:33 2004

Total 1 displayed, Up 1, Down 0

[...Output truncated...]

What It Means

Lines 1through 6 contain the six most recent entries to the history log. Each line is time stamped. The most recent entries have the largest log history number and are at the top of the log, indicating that line 6 is the most recent entry in the history log.

The history log was started on August 17, and displays the following sequence of activities: a call failed because the address could not be reached (line 1); 31 seconds later, probably because the addressing problem was resolved, the call was signaled (line 2); the call was completed (line 3); the LSP came up with a route (lines 4 and 5); and the LSP was selected as active (line 6).

For more details about the messages that can appear in the history log, see JUNOS MPLS Operations Guide: Log Files.