Service Manual

Figure 104. Priority and Cost Examples
OSPF with Dell EMC Networking OS
The Dell EMC Networking OS supports up to 128,000 OSPF routes for OSPFv2.
Dell EMC Networking OS version 9.4(0.0) and later support only one OSPFv2 process per VRF. Dell EMC Networking OS
version 9.7(0.0) and later support OSPFv3 in VRF. Also, on OSPFv3, Dell EMC Networking OS supports only one OSPFv3
process per VRF.
OSPFv2 and OSPFv3 can co-exist but you must configure them individually.
Dell EMC Networking OS supports stub areas, totally stub (no summary) and not so stubby areas (NSSAs) and supports the
following LSAs, as described earlier.
● Router (type 1)
● Network (type 2)
● Network Summary (type 3)
● AS Boundary (type 4)
● LSA(type 5)
● External LSA (type 7)
● Link LSA, OSPFv3 only (type 8)
● Opaque Link-Local (type 9)
● Grace LSA, OSPFv3 only (type 11)
Graceful Restart
When a router goes down without a graceful restart, there is a possibility for loss of access to parts of the network due to
ongoing network topology changes. Additionally, LSA flooding and reconvergence can cause substantial delays. It is, therefore,
desirable that the network maintains a stable topology if it is possible for data flow to continue uninterrupted.
OSPF graceful restart understands that in a modern router, the control plane and data plane functionality are separate,
restarting the control plane functionality (such as the failover of the active RPM to the backup in a redundant configuration),
Open Shortest Path First (OSPFv2 and OSPFv3)
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