Passive Interfaces; Graceful Restart - Dell Networking 2024 Reference Manual

Passive Interfaces

The passive interface feature is used to disable sending OSPF routing updates
on an interface. An OSPF adjacency will not be formed on such an interface.
On a passive interface, subnet prefixes for IP addresses configured on the
interface will continue to be advertised as stub networks.

Graceful Restart

The Dell Networking implementation of OSPFv2 supports graceful restart as
specified in RFC 3623. Graceful restart works in concert with Dell
Networking nonstop forwarding to enable the hardware to continue
forwarding IPv4 packets using OSPFv2 routes while a backup unit takes over
management unit responsibility. When OSPF executes a graceful restart, it
informs its neighbors that the OSPF control plane is restarting, but that it
will be back shortly. Helpful neighbors continue to advertise to the rest of the
network that they have full adjacencies with the restarting router, avoiding
announcement of a topology change and everything that goes with that (i.e.,
flooding of LSAs, SPF runs). Helpful neighbors continue to forward packets
through the restarting router. The restarting router relearns the network
topology from its helpful neighbors.
Dell Networking implements both the restarting router and helpful neighbor
features described in RFC 3623.
Commands in this Chapter
This chapter explains the following commands:
area default-cost
(Router OSPF)
area nssa (Router
OSPF)
area nssa default-
info-originate
(Router OSPF
Config)
1194
OSPF Commands
capability opaque
clear ip ospf
clear ip ospf stub-
router
ip ospf priority
ip ospf retransmit-
interval
ip ospf transmit-
delay
show ip ospf asbr
show ip ospf database
show ip ospf database
database-summary