Switch 7700 Configuration Guide, v2

OSPF 85
By default, LSU packets are transmitted by seconds.
Set an Interval for LSA Retransmission Between Neighboring Routers
If a router transmits an LSA to the peer, it requires the acknowledgement packet
from the peer. If it does not receive the acknowledgement packet within the
retransmission, it retransmits this LSA to the neighbor. You can configure the value
of the retransmission interval.
Perform the following configuration in VLAN interface view.
By default, the interval for neighboring routers to retransmit LSAs is five seconds.
The value of the interval should be bigger than the interval in which a packet can
be transmitted and returned between two routers.
Note that a LSA retransmission interval that is too small will cause unnecessary
retransmission.
Set a Shortest Path First (SPF) Calculation Interval for OSPF
Whenever the OSPF LSDB changes, the shortest path requires recalculation.
Calculating the shortest path after a change consumes enormous resources and
affects the operating efficiency of the router. Adjusting the SPF calculation interval,
however, can restrain the resource consumption caused by frequent network
changes.
Perform the following configuration in OSPF view.
By default, the interval FOR SPF recalculation is 5 seconds.
Configure the OSPF STUB Area
STUB areas are special LSA areas in which the ABRs do not propagate the learned
external routes of the AS. In these areas, the routing table sizes of routers and the
routing traffic are significantly reduced.
The STUB area is an optional configuration attribute, but not every area conforms
to the configuration condition. Generally, STUB areas, located at the AS
boundaries, are those non-backbone areas with only one ABR. Even if this area has
multiple ABRs, no virtual links are established between these ABRs.
Table 33 Set Retransmit Timer
Operation Command
Configure the interval of LSA
retransmission for the
neighboring routers
ospf timer retransmit interval
Restore the default LSA
retransmission interval for the
neighboring routers
undo ospf timer retransmit
Table 34 Set the SPF Calculation Interval
Operation Command
Set the SPF calculation interval spf-schedule-interval seconds
Restore the SPF calculation interval undo spf-schedule-interval seconds