3Com Switch 7750 Series
Command Reference Guide – Routing Protocol Chapter 4 Integrated IS-IS Configuration Commands
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4.1.43 timer spf Syntax
timer spf seconds [ level-1 | level-2 ]
undo timer spf [ level-1 | level-2 ]
View
IS-IS view
Parameter
seconds: Maximum time interval (in seconds) for SPF calculation, ranging from 1 to
120, with the default as 10.
level-1: Specifies to set the time interval for only Level-1 SPF calculation.
level-2: Specifies to set the time interval for only Level-2 SPF calculation.
If neither the level-1 keyword nor the level-2 keyword is specified, the interval of both
level-1 SPF calculation and the level-2 SPF calculation are set.
Description
Use the timer spf command to set the time interval for SPF calculation.
Use the undo timer spf command to resume the default configuration.
In the IS-IS protocol, the short path must be calculated again when the LSDB changes.
If the SPF calculation is performed frequently, plenty of system resources will be
occupied and the router efficiency will be affected. Comparatively, performing SPF
calculation periodically can improve the efficiency. You can set the time interval of
performing SPF calculation as required.
Example
# Set the time interval of performing SPF calculation to three seconds.
<3Com> system-view
System View: return to User View with Ctrl+Z.
[3Com] isis
[3Com-isis] timer spf 3