Configuring Spf Parameters - H3C S7500 Series Operation Manual

Operation Manual – Routing Protocol
H3C S7500 Series Ethernet Switches
To do...
Assign an LSP
maximum aging
time

5.3.23 Configuring SPF Parameters

I. Configuring the SPF interval
In IS-IS, a router needs to recalculate the shortest path when the LSDB changes.
Recalculating the shortest path upon change consumes enormous resources as well
as affects the operation efficiency of the router. With an SPF calculation interval
configured, when the LSDB changes, the SPF algorithm is not executed until the SPF
timer expires.
Follow these steps to configure the SPF interval:
Enter system view
Enter IS-IS view
Configure the SPF
interval
Note:
If you do not provide the level-1 or level-2 keyword, this command applies to Level-1
and Level-2 by default.
II. Configuring SPF calculation durations
SPF calculation in IS-IS may occupy system resources for a long time if the routing
table contains a great number of entries (over 30,000). To avoid this, you can
configure SPF calculation durations.
Follow these steps to configure SPF calculation durations:
Enter system view
Enter IS-IS view
Use the command...
timer lsp-max-age
seconds
To do...
system-view
isis [ tag ]
timer spf seconds
[ level-1 | level-2 ]
To do...
system-view
isis [ tag ]
Required
By default, the LSP maximum
aging time is 1,200 seconds,
namely, 20 minutes.
Use the command...
Use the command...
5-21
Chapter 5 IS-IS Configuration
Remarks
Remarks
—
—
Required
The default SPF interval is
10 seconds.
Remarks
—
—