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The fast convergence
default optimize feature modifies the default settings of all the protocols to
recommended defaults for fast convergence.
Feature Information
for Fast Convergence Default Optimize
The following table provides release information about the feature or features described in this module. This table lists
only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise,
subsequent releases of that software release train also support that feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco
Feature Navigator, go to https://cfnng.cisco.com/. An account on Cisco.com is not required.
Table 1. Feature Information for Fast Convergence Default Optimize
Feature Name
Releases
Feature Information
Fast Convergence Default Optimize
Cisco IOS XE Amsterdam 17.3.2
The fast convergence default optimize feature modifies the
default settings of all the protocols to recommended defaults for fast
convergence.
No new commands were added or modified.
Information About
Fast Convergence Default Optimize
The fast convergence
default optimize feature modifies the default settings of all the protocols to
recommended defaults for fast convergence. To revert the defaults to
pre-fast-convergence settings for both IS-IS and OSPF,
no
routing-default-optimize command is used. This command sends
signals to IS-IS and OSPF and modifies the default configuration for these
protocols.
By default, the fast
convergence settings is enabled which means when you upgrade the software, you
can automatically see the new behavior. This makes easier integration of the
devices in a multi-vendor deployment and reduces support cases for poor
convergence.
When default optimize
is disabled, existing protocol default configuration is used. When default
optimize is enabled, new protocol defaults are used. The show running
configurations does not display configuration lines for default settings even
when default settings are being used.
A configuration of a
protocol overrides the default, but a change to default optimize does not
override any configuration.
The following is the
sample output of
spf-interval
command in IS-IS:
If a non-default value
is configured, it will be displayed in show running configuration output:
Device(config-router)# spf-interval 5 50 200
Device(config-router)# do show run | inc spf-interval
spf-interval 5 50 200
You can revert to the
default values by configuring the default values or by removing the non-default
configuration.
Default Optimize Values for IS-IS
The following table summarizes the configuration impacted by default optimize:
IS-IS command
Parameters
Default optimize disabled
Default optimize enabled
fast-flood
# of lsps flooded back-back
Disabled
10
spf-interval
Initial (milliseconds)
5500
50
Secondary (milliseconds)
5500
200
max (seconds)
10
5
prc-interval
Initial (milliseconds)
2000
50
Secondary (milliseconds)
5000
200
max (seconds)
5
5
lsp-gen-interval
Initial (milliseconds)
50
50
Secondary (milliseconds)
5000
200
max (seconds)
5
5
log-adjacency-changes
disabled
enabled
Default Optimize Values for OSPF
The following table summarizes the configuration impacted by default optimize for OSPFv2/v3:
OSPF command
Parameters
Default optimize disabled
Default optimize enabled
timers throttle spf
Initial (milliseconds)
5000
50
Secondary (milliseconds)
10000
200
max (milliseconds)
10
5
timers throttle lsa all
Initial (milliseconds)
0
50
Secondary (milliseconds)
5000
200
max (milliseconds)
5
5
timers lsa arrival
milliseconds
1000
100
The following is the sample output of show ip ospf command for OSPFv2 with the default-optimize values.
Device# show ip ospf
Routing Process "ospf 10" with ID 10.1.1.1
Start time: 00:00:01.471, Time elapsed: 03:00:34.706
Supports only single TOS(TOS0) routes
Supports opaque LSA
Supports Link-local Signaling (LLS)
Supports area transit capability
Supports NSSA (compatible with RFC 3101)
Supports Database Exchange Summary List Optimization (RFC 5243)
Event-log enabled, Maximum number of events: 1000, Mode: cyclic
Router is not originating router-LSAs with maximum metric
Initial SPF schedule delay 50 msecs
Minimum hold time between two consecutive SPFs 200 msecs
Maximum wait time between two consecutive SPFs 5000 msecs
Incremental-SPF disabled
Initial LSA throttle delay 50 msecs
Minimum hold time for LSA throttle 200 msecs
Maximum wait time for LSA throttle 5000 msecs
Minimum LSA arrival 100 msecs
LSA group pacing timer 240 secs
Interface flood pacing timer 33 msecs
Retransmission pacing timer 66 msecs
EXCHANGE/LOADING adjacency limit: initial 300, process maximum 300
Number of external LSA 18. Checksum Sum 0x075EB2
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Number of areas transit capable is 0
External flood list length 0
IETF NSF helper support enabled
Cisco NSF helper support enabled
Reference bandwidth unit is 100 mbps
Area BACKBONE(0)
Number of interfaces in this area is 4 (2 loopback)
Area has RRR enabled
Area has no authentication
SPF algorithm last executed 02:27:23.736 ago
SPF algorithm executed 20 times
Area ranges are
Number of LSA 94. Checksum Sum 0x321DCF
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
The following is the sample output of show ospf command for OSPFv3 with the default-optimize values.
Device# show ospfv3
OSPFv3 10 address-family ipv6
Router ID 10.11.11.11
Supports NSSA (compatible with RFC 3101)
Supports Database Exchange Summary List Optimization (RFC 5243)
Event-log enabled, Maximum number of events: 1000, Mode: cyclic
Router is not originating router-LSAs with maximum metric
Initial SPF schedule delay 50 msecs
Minimum hold time between two consecutive SPFs 200 msecs
Maximum wait time between two consecutive SPFs 5000 msecs
Initial LSA throttle delay 50 msecs
Minimum hold time for LSA throttle 200 msecs
Maximum wait time for LSA throttle 5000 msecs
Minimum LSA arrival 100 msecs
LSA group pacing timer 240 secs
Interface flood pacing timer 33 msecs
Retransmission pacing timer 66 msecs
Retransmission limit dc 24 non-dc 24
EXCHANGE/LOADING adjacency limit: initial 300, process maximum 300
Number of external LSA 0. Checksum Sum 0x000000
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Graceful restart helper support enabled
Reference bandwidth unit is 100 mbps
RFC1583 compatibility enabled
Area BACKBONE(0)
Number of interfaces in this area is 2
SPF algorithm executed 7 times
Number of LSA 3. Checksum Sum 0x012426
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
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