Connectivity Guide

Table Of Contents
OSPF route limit
OS10 supports up to 16,000 OSPF routes. Within this range, the only restriction is on intra-area routes that scale only up to 1000 routes.
Other OSPF routes can scale up to 16 K.
Shortest path rst throttling
Use shortest path rst (SPF) throttling to delay SPF calculations during periods of network instability. In an OSPF network, a topology
change event triggers an SPF calculation that is performed after a start time. When the start timer nishes, a hold time can delay the next
SPF calculation for an additional time.
When the hold timer is running:
Each time a topology change occurs, the SPF calculation delays for double the congured hold time up to maximum wait time.
If no topology change occurs, an SPF calculation is performed and the hold timer is reset to its congured value.
Set the start, hold, and wait timers according to the stability of the OSPF network topology. Enter the values in milliseconds (ms). If you do
not specify a start-time, hold-time, or max-wait value, the default values are used.
OSPFv2 and OSPFv3 instances support SPF throttling. By default, SPF timers are disabled in an OSPF instance. Enter the no version of
this command to remove the congured SPF timers and disable SPF throttling.
1 Congure an OSPF instance from CONFIGURATION mode, from 1 to 65535.
router {ospf | ospfv3} instance-number
2 Set OSPF throttling timers in OSPF INSTANCE mode.
timers spf [start-time [hold-time [max-wait]]]
start-timeCongure the initial delay before performing an SPF calculation after a topology change, from 1 to 600000
milliseconds; default 1000.
hold-timeCongure the additional delay before performing an SPF calculation when a new topology change occurs, from 1
to 600000 milliseconds; default 10000.
max-waitCongure the maximum amount of hold time that can delay an SPF calculation, from 1 to 600000 milliseconds;
default 10000.
Enable SPF throttling (OSPFv2)
OS10(config)# router ospf 100
OS10(config-router-ospf-100)# timers spf 1200 2300 3400
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Layer 3