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Usage guidelines
Based on the LSDB, an IS-IS router uses the SPF algorithm to calculate a shortest path tree with itself being
the root, and uses the shortest path tree to determine the next hop to a destination network. By adjusting
the SPF calculation interval, you can prevent bandwidth and router resources from being overused due
to frequent topology changes.
When network changes are not frequent, the
minimum-interval is
adopted
.
If network changes become
frequent, the SPF calculation interval is incremented by the
incremental-interval
each time a generation
happens until the
maximum-interval
is reached.
The minimum interval and the incremental interval cannot be greater than the maximum interval.
Examples
# Configure the maximum interval as 10 seconds, the minimum interval as 100 milliseconds, and the
incremental interval as 300 milliseconds.
<Sysname> system-view
[Sysname] isis 1
[Sysname-isis-1] timer spf 10 100 300
virtual-system
Use
virtual-system
to configure a virtual system ID for the IS-IS process.
Use
undo virtual-system
to remove a virtual system ID.
Syntax
virtual-system
virtual-system-id
undo virtual-system
virtual-system-id
Default
No virtual system ID is configured.
Views
IS-IS view
Predefined user roles
network-admin
Parameters
virtual-system-id
: Specifies a virtual system ID for the IS-IS process.
Examples
# Set a virtual system ID of 2222.2222.2222 for IS-IS process 1.
<Sysname> system-view
[Sysname] isis 1
[Sysname-isis-1] virtual-system 2222.2222.2222