Reference Guide

Setting the convergence parameter (from 1 to 4) indicates the actual convergence level. Each convergence setting
adjusts the LSA parameters to zero, but the fast-convergence parameter setting allows for even finer tuning of the
convergence speed. The higher the number, the faster the convergence.
To enable or disable fast-convergence, use the following command.
• Enable OSPF fast-convergence and specify the convergence level.
CONFIG-ROUTEROSPF- id mode
fast-convergence {number}
The parameter range is from 1 to 4.
The higher the number, the faster the convergence.
When disabled, the parameter is set at 0.
NOTE: A higher convergence level can result in occasional loss of OSPF adjacency. Generally, convergence
level 1 meets most convergence requirements. Only select higher convergence levels following consultation
with Dell Technical Support.
In the examples below, Convergence Level shows the fast-converge parameter setting and Min LSA
origination shows the LSA parameters (shown in bold).
Example of the fast-converge Command
FTOS(conf-router_ospf-1)#fast-converge 2
FTOS(conf-router_ospf-1)#ex
FTOS(conf)#ex
FTOS#show ip ospf 1
Routing Process ospf 1 with ID 192.168.67.2
Supports only single TOS (TOS0) routes
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Convergence Level 2
Min LSA origination 0 secs, Min LSA arrival 0 secs
Number of area in this router is 0, normal 0 stub 0 nssa 0
FTOS#
Example of Disabling Fast-Convergence
FTOS#(conf-router_ospf-1)#no fast-converge
FTOS#(conf-router_ospf-1)#ex
FTOS#(conf)#ex
FTOS##show ip ospf 1
Routing Process ospf 1 with ID 192.168.67.2
Supports only single TOS (TOS0) routes
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Convergence Level 0
Min LSA origination 5 secs, Min LSA arrival 1 secs
Number of area in this router is 0, normal 0 stub 0 nssa 0
FTOS#
Changing OSPFv2 Parameters on Interfaces
In FTOS, you can modify the OSPF settings on the interfaces.
Some interface parameter values must be consistent across all interfaces to avoid routing errors. For example, set the
same time interval for the hello packets on all routers in the OSPF network to prevent misconfiguration of OSPF
neighbors.
To change OSPFv2 parameters on the interfaces, use any or all of the following commands.
• Change the cost associated with OSPF traffic on the interface.
CONFIG-INTERFACE mode
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