Dell N1100-ON, Reference Manual

Page: 1711 / 2332

Layer 3 Routing Commands
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User Guidelines
OSPF distributes routing information in Link State Advertisements (LSAs),
which are bundled into Link State Update (LS Update) packets. To reduce
the likelihood of sending a neighbor more packets than it can buffer, OSPF
rate limits the transmission of LS Update packets. By default, OSPF sends up
to 30 updates per second on each interface (1/the pacing interval). Use this
command to adjust the LS Update transmission rate.
timers pacing lsa-group
Use the timers pacing lsa-group command to tune how OSPF groups LSAs
for periodic refresh.
Syntax
timers pacing lsa-group seconds
• seconds—Width of the window in which LSAs are refreshed. The range for
the pacing group window is from 10 to 1800 seconds.
Default Configuration
The default timer pacing is 60 seconds.
Command Mode
OSPFv2 Global Configuration mode
User Guidelines
OSPF refreshes self-originated LSAs approximately once every 30 minutes.
When OSPF refreshes LSAs, it considers all self-originated LSAs whose age is
from 1800 to 1800 plus the pacing group size. Grouping LSAs for refresh
allows OSPF to combine refreshed LSAs into a minimal number of LS
Update packets. Minimizing the number of Update packets makes LSA
distribution more efficient.
When OSPF originates a new or changed LSA, it selects a random refresh
delay for the LSA. When the refresh delay expires, OSPF refreshes the LSA.
By selecting a random refresh delay, OSPF avoids refreshing a large number of
LSAs at one time, even if a large number of LSAs are originated at one time.