display isis spf-log frr

Function

The display isis spf-log frr command displays the SPF calculation log of IS-IS.

Format

display isis spf-log [ process-id ] frr [ ipv6 | [ level-1 | level-2 ] ] ^*

Parameters

Parameter	Description	Value
process-id	Specifies an IS-IS process ID.	The value is an integer ranging from 1 to 4294967295.
frr	Indicates the FRR calculation log.	-
ipv6	Indicates the SPF calculation log in the IPv6 topology.	-
level-1	Indicates the SPF calculation log in a Level-1 area.	-
level-2	Indicates the SPF calculation log in a Level-2 area.	-

Views

All views

Default Level

1: Monitoring level

Task Name and Operations

Task Name	Operations
isis	read

Usage Guidelines

Usage Scenario

When an error occurs in the IS-IS SPF calculation, run the display isis spf-log command to diagnose the fault. The command can be used to view the SPF calculation log of IS-IS, such as the start time, duration, number of nodes, and events that trigger the SPF calculation. You can check which event causes the error of the SPF calculation by the start time.

Check the StartTime field first. If the SPF calculation is performed repeatedly at short intervals, flapping may have occurred. Then check the Last Trigger LSP and Trigger Event fields for further analysis.

Example

The actual command output varies according to the device. The command output here is only an example.

# Display the FRR calculation log.

<HUAWEI> display isis spf-log frr

                        SPF Log information for ISIS(1)
                        -------------------------------

                            ISIS(1) Level-1 FRR Log
                            -----------------------

 StartTime  Duration  Nodes  Count  Last Trigger LSP      Trigger Event        
-------------------------------------------------------------------------------
2019-08-10  0         1      1      NULL                  L1_IFRR_CIRC_METRIC_C
08:28:14.99                                               HANGE                
6                                                                              
2019-08-10  1         1      1      NULL                  L1_IFRR_CIRC_METRIC_C
08:12:34.75                                               HANGE                
7

**Table 1** Description of the **display isis spf-log frr** command output
Item	Description
StartTime	Start time for SPF calculation.
Duration	Time taken for SPF calculation, the value rounds down the actual duration, in milliseconds. In most cases, the value is less than 1 ms. Therefore, it is displayed as 0.
Nodes	Number of nodes calculated by SPF.
Count	Number of events triggering the SPF calculation.
Last Trigger LSP	LSP that triggers the last SPF calculation.
Trigger Event	Event that triggers the last SPF calculation.