Reference Guide

Configuring LSA Throttling Timers
Configured link-state advertisement (LSA) timers replace the standard transmit and acceptance times for LSAs.
The LSA throttling timers are configured in milliseconds. The interval time increases exponentially until a maximum time is
reached. If the maximum time is reached, the system continues to transmit at the maximum interval. If the system is stable for
twice the maximum interval time, it reverts to the start-interval timer. The cycle repeats.
To configure the LSA throttling timers, use the following commands.
1. Specify the interval times for all LSA transmissions. CONFIG-ROUTER-OSPF-id mode. timers throttle lsa all
{start-interval | hold-interval | max-interval} To set the minimum interval between initial sending and
resending the same LSA, use the keywords start-interval. To set the next interval to send the same LSA, use the
keywords hold-interval. The hold-interval is the time between sending the same LSA after the start-interval is
attempted. To set the maximum amount of time the system waits before sending the LSA, use the keywords max-
interval. The interval range is 0 to 600,000 milliseconds.
2. Specify the interval for LSA acceptance. CONFIG-ROUTER-OSPF-id mode. timers throttle lsa all arrival-
time
Enabling Passive Interfaces
A passive interface is one that does not send or receive routing information.
Enabling passive interface suppresses routing updates on an interface. Although the passive interface does not send or receive
routing updates, the network on that interface is still included in OSPF updates sent via other interfaces.
To suppress the interface’s participation on an OSPF interface, use the following command. This command stops the router
from sending updates on that interface.
● Specify whether all or some of the interfaces are passive.
CONFIG-ROUTEROSPF- id mode
passive-interface {default | interface}
The default is enabled passive interfaces on ALL interfaces in the OSPF process.
Entering the physical interface type, slot, and number enables passive interface on only the identified interface.
○ For a 10–Gigabit Ethernet interface, enter the keyword TenGigabitEthernet then the slot/port information (for
example, passive-interface te 2/1).
○ For a port channel, enter the keywords port-channel then a number from 1 to 255 for TeraScale and ExaScale.
○ For a 40-Gigabit Ethernet interface, enter the keyword FortyGigabitEthernet then the slot/port information (for
example, passive-interface fo 2/3).
○ For a VLAN, enter the keyword vlan then a number from 1 to 4094 (for example, passive-interface vlan
2222).
The keyword default sets all interfaces on this OSPF process as passive.
To remove the passive interface from select interfaces, use the no passive-interface interface command while
passive interface default is configured.
To enable both receiving and sending routing updates, use the no passive-interface interface command.
When you configure a passive interface, the show ip ospf process-id interface command adds the words passive
interface to indicate that the hello packets are not transmitted on that interface (shown in bold).
Dell#show ip ospf 34 int
TengigabitEthernet 0/0 is up, line protocol is down
Internet Address 10.1.2.100/24, Area 1.1.1.1
Process ID 34, Router ID 10.1.2.100, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DOWN, Priority 1
Designated Router (ID) 10.1.2.100, Interface address 0.0.0.0
Backup Designated Router (ID) 0.0.0.0, Interface address 0.0.0.0
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 13:39:46
Neighbor Count is 0, Adjacent neighbor count is 0
TengigabitEthernet 0/1 is up, line protocol is down
534
Open Shortest Path First (OSPFv2 and OSPFv3)