R21xx-HP FlexFabric 11900 Layer 3 IP Routing Command Reference

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Usage guidelines
Based on the LSDB, an OSPF router uses SPF to calculate a shortest path tree with itself as the root. OSPF
uses the shortest path tree to determine the next hop to a destination. By adjusting the SPF calculation
interval, you can prevent bandwidth and router resources from being over-consumed due to frequent
topology changes.
When network changes are not frequent, OSPF performs SPF calculations at the minimum-interval. If
network changes become frequent, the SPF calculation interval is incremented by the incremental-interval
each time a calculation 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 SPF calculation interval as 10 seconds, minimum interval as 500 milliseconds
and incremental interval as 300 milliseconds.
<Sysname> system-view
[Sysname] ospf 100
[Sysname-ospf-100] spf-schedule-interval 10 500 300
stub (OSPF area view)
Use stub to configure an area as a stub area.
Use undo stub to restore the default.
Syntax
stub [ default-route-advertise | no-summary ] *
undo stub
Default
No area is a stub area.
Views
OSPF area view
Predefined user roles
network-admin
Parameters
default-route-advertise-always: Usable only on a stub ABR. With this keyword, the ABR advertises a
default route in a Type-3 LSA into the stub area regardless of whether FULL-state neighbors exist in the
backbone area. Without this keyword, the ABR advertises a default route in a Type-3 LSA into the stub
area only when at least one FULL-state neighbor exists in the backbone area.
no-summary: Usable only on a stub ABR. With this keyword, the ABR advertises only a default route in
a Type-3 LSA into the stub area without advertising any other Type-3 LSAs (such a stub area is a totally
stub area).
Usage guidelines
To remove the default-route-advertise-always or stub no-summary configuration on the ABR, execute the
stub command again to overwrite it.
To configure an area as a stub area, issue the stub command on all routers attached to the area.