Administrator Guide

Layer 3 Routing Commands 1800
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.
timers spf
Use the timers spf command in Router OSPF Configuration mode to
configure the SPF delay and hold time. Use the no form of the command to
reset the numbers to the default value.
Syntax
timers spf delay-time hold-time
no timers spf
• delay-time — SPF delay time. (Range: 0–65535 seconds)
•
hold-time — SPF hold time. (Range: 0–65535 seconds)
Default Configuration
The default value for delay-time is 5. The default value for hold-time is 10.
Command Mode
Router OSPF Configuration mode.
User Guidelines
This command has no user guidelines.
Example
The following example configures the SPF delay and hold time.
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