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Parameters
maximum-interval
: Maximum SPF calculation interval in seconds, ranging from 1 to 120.
initial-interval
: Wait interval before the first SPF calculation, in milliseconds, ranging from 10 to 60000.
second-interval
: Wait interval before the second SPF calculation, in milliseconds, ranging from 10 to
60000.
Description
Use the
timer spf
command to set the SPF calculation interval.
Use the
undo timer spf
command to restore the default.
The default IS-IS SPF calculation interval is 10 seconds.
Note that:
1) If only the maximum interval is specified, IS-IS waits the maximum interval before performing the
SPF calculation.
2) If both the maximum and initial intervals are specified:
z
IS-IS waits the initial interval before performing the first SPF calculation.
z
When SPF calculation triggers occur at intervals shorter than the maximum interval, the topology
is considered unstable and IS-IS waits the maximum interval before performing the SPF
calculation until the topology is stable.
3) If
maximum-interval
,
initial-interval
, and
second-interval
are specified:
z
IS-IS waits the initial interval before performing the first SPF calculation.
z
When SPF calculation triggers occur at intervals shorter than the maximum interval, the topology
is considered unstable, IS-IS will wait the
second-interval
before performing the second SPF
calculation and penalty is applied on the wait interval for the next SPF calculation. That is, for
each subsequent trigger, the wait interval before SPF calculation will be two times the previous
wait interval until the maximum interval is reached.
z
After the network topology becomes stable; that is, triggers occur at intervals greater than the
maximum interval, the wait interval before SPF calculation is restored to the initial interval.
Examples
# Configure the maximum SPF calculation interval as 10 seconds, the wait interval before the first SPF
calculation as 100 milliseconds, and the wait interval before the second SPF calculation as 200
milliseconds.
<Sysname> system-view
[Sysname] isis 1
[Sysname-isis-1] timer spf 10 100 200
virtual-system
Syntax
virtual-system
virtual-system-id
undo virtual-system
virtual-system-id
View
IS-IS view