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.
Examples of Enabling Fast-Convergence
In the following examples, Convergence Level shows the fast-converge parameter setting and Min
LSA origination shows the LSA parameters (shown in bold).
The following example shows the fast-converge command.
Dell(conf-router_ospf-1)#fast-converge 2
Dell(conf-router_ospf-1)#ex
Dell(conf)#ex
Dell#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
Dell#
To disable fast-convergence, use the no fast-converge command.
Dell#(conf-router_ospf-1)#no fast-converge
Dell#(conf-router_ospf-1)#ex
Dell#(conf)#ex
Dell##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
Dell#
Changing OSPFv2 Parameters on Interfaces
You can modify the OSPF configuration on switch 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
ip ospf cost
–cost: The range is from 1 to 65535 (the default depends on the interface speed).
• Change the time interval the router waits before declaring a neighbor dead.
CONFIG-INTERFACE mode
ip ospf dead-interval seconds
–seconds: the range is from 1 to 65535 (the default is 40 seconds).
The dead interval must be four times the hello interval.
638 Open Shortest Path First (OSPFv2 and OSPFv3)