Dell Z9500 Configuration Manual page 588

Enabling Fast-Convergence
The fast-convergence CLI sets the minimum origination and arrival LSA parameters to zero (0), allowing rapid route calculation.
When you disable fast-convergence, origination and arrival LSA parameters are set to 5 seconds and 1 second, respectively.
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.
Examples of the fast-converge Command
In the following examples, Convergence Level shows the fast-converge parameter setting and Min LSA origination
shows the LSA parameters (shown in bold).
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#
The following examples shows how to disable fast-convergence.
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
In Dell Networking OS, 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.
Open Shortest Path First (OSPFv2 and OSPFv3) 588