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fast-convergence
This command sets the minimum LSA origination and arrival times to zero (0), allowing more rapid route computation so that
convergence takes less time.
Syntax
fast-convergence {number}
To cancel fast-convergence, use the no fast convergence command.
Parameters
number Enter the convergence level desired. The higher this parameter is set, the faster
OSPF converge takes place. The range is from 1 to 4.
Defaults none.
Command Modes ROUTER OSPF
Supported Modes Full—Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
8.3.16.1 Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
The higher this parameter is set, the faster OSPF converge takes place.
NOTE: The faster the convergence, the more frequent the route calculations and updates. This
behavior impacts CPU utilization and may impact adjacency stability in larger topologies.
Generally, convergence level 1 meets most convergence requirements. Higher convergence levels should
only be selected following consultation with Dell Networking technical support.
flood-2328
Enable RFC-2328 flooding behavior.
Syntax
flood-2328
To disable, use the no flood-2328 command.
Defaults Disabled.
Command Modes ROUTER OSPF
Supported Modes Full—Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
8.3.16.1 Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
In OSPF, flooding is the most resource-consuming task. The flooding algorithm, described in RFC-2328,
requires that OSPF flood LSAs (Link State Advertisements) on all interfaces, as governed by LSA’s
flooding scope (see Section 13 of the RFC). When multiple direct links connect two routers, the
RFC-2328 flooding algorithm generates significant redundant information across all links.
By default, the system implements an enhanced flooding procedure that dynamically and intelligently
determines when to optimize flooding. Whenever possible, the OSPF task attempts to reduce flooding
overhead by selectively flooding on a subset of the interfaces between two routers.
When you enable flood-2328, this command configures the system to flood LSAs on all interfaces.
Open Shortest Path First (OSPFv2 and OSPFv3) 805