Set Spf Interval For A Single-Topology Configuration - Cisco NCS 5500 Series Configuration Manuals

Set SPF Interval for a Single-Topology Configuration

Configuring Single-Topology IS-IS for IPv6: Example
The following example shows single-topology mode being enabled. An IS-IS instance is created,
the NET is defined, IPv6 is configured along with IPv4 on an interface, and IPv4 link topology is
used for IPv6. This configuration allows POS interface 0/3/0/0 to form adjacencies for both IPv4
and IPv6 addresses.
router isis isp
net 49.0000.0000.0001.00
address-family ipv6 unicast
interface POS0/3/0/0
!
interface POS0/3/0/0
ipv4 address 10.0.1.3 255.255.255.0
ipv6 address 2001::1/64
Set SPF Interval for a Single-Topology Configuration
This task explains how to make adjustments to the SPF calculation to tune router performance. This task is
optional.
Because the SPF calculation computes routes for a particular topology, the tuning attributes are located in the
router address family configuration submode. SPF calculation computes routes for Level 1 and Level 2
separately.
When IPv4 and IPv6 address families are used in a single-topology mode, only a single SPF for the IPv4
topology exists. The IPv6 topology "borrows" the IPv4 topology; therefore, no SPF calculation is required
for IPv6. To tune the SPF calculation parameters for single-topology mode, configure the address-family
ipv4 unicast command.
The incremental SPF algorithm can be enabled separately. When enabled, the incremental shortest path first
(ISPF) is not employed immediately. Instead, the full SPF algorithm is used to "seed" the state information
required for the ISPF to run. The startup delay prevents the ISPF from running for a specified interval after
an IS-IS restart (to permit the database to stabilize). After the startup delay elapses, the ISPF is principally
responsible for performing all of the SPF calculations. The reseed interval enables a periodic running of the
full SPF to ensure that the iSFP state remains synchronized.
SUMMARY STEPS
1. configure
2. router isis instance-id
3. address-family { ipv4 | ipv6 } [ unicast ]
4. spf-interval {[ initial-wait initial | secondary-wait secondary | maximum-wait maximum ] ...}
[ level { 1 | 2 }]
5. ispf [ level { 1 | 2 }]
6. commit
Routing Configuration Guide for Cisco NCS 5500 Series Routers, IOS XR Release 6.3.x
10
single-topology
address-family ipv4 unicast
!
address-family ipv6 unicast
!
exit
Implementing IS-IS