Concept Guide
• Grace LSA, OSPFv3 only (type 11)
Fast Convergence (OSPFv2, IPv4 Only)
Fast convergence allows you to dene the speeds at which LSAs are originated and accepted, and reduce OSPFv2 end-to-end
convergence time.
The system allows you to accept and originate LSAs as soon as they are available to speed up route information propagation.
NOTE: The faster the convergence, the more frequent the route calculations and updates. This impacts CPU utilization and may
impact adjacency stability in larger topologies.
Multi-Process OSPFv2 (IPv4 only)
Multi-process OSPF is supported only on OSPFv2 with IPv4 on the switch. Up to 32 OSPFv2 processes are supported.
Multi-process OSPF allows multiple OSPFv2 processes on a single router. Multiple OSPFv2 processes allow for isolating routing domains,
supporting multiple route policies and priorities in dierent domains, and creating smaller domains for easier management.
Each OSPFv2 process has a unique process ID and must have an associated router ID. There must be an equal number of interfaces and
must be in Layer-3 mode for the number of processes created. For example, if you create ve OSPFv2 processes on a system, there must
be at least ve interfaces assigned in Layer 3 mode.
Each OSPFv2 process is independent. If one process loses adjacency, the other processes continue to function.
Processing SNMP and Sending SNMP Traps
Though there are may be several OSPFv2 processes, only one process can process simple network management protocol (SNMP)
requests and send SNMP traps.
The mib-binding command identies one of the OSPVFv2 processes as the process responsible for SNMP management. If you do not
specify the
mib-binding command, the rst OSPFv2 process created manages the SNMP processes and traps.
RFC-2328 Compliant OSPF Flooding
In OSPF, ooding is the most resource-consuming task. The ooding algorithm described in RFC 2328 requires that OSPF ood LSAs on all
interfaces, as governed by LSA’s ooding scope (refer to Section 13 of the RFC.)
When multiple direct links connect two routers, the RFC 2328 ooding algorithm generates signicant redundant information across all
links.
By default, the system implements an enhanced ooding procedure which dynamically and intelligently detects when to optimize ooding.
Wherever possible, the OSPF task attempts to reduce ooding overhead by selectively ooding on a subset of the interfaces between two
routers.
Enabling RFC-2328 Compliant OSPF Flooding
To enable OSPF ooding, use the following command.
When you enable this command, it congures the system to ood LSAs on all interfaces.
• Enable RFC 2328 ooding.
ROUTER OSPF mode
flood-2328
Open Shortest Path First (OSPFv2 and OSPFv3)
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