ip ospf dead-interval

Configures the neighbor dead interval, which is the number of seconds that a neighbor router waits for a hello packet from the device before declaring the router down.
Syntax
ip ospf dead-intervalinterval
no ip ospf dead-interval
Command Default

The specified time period is 40 seconds.

Parameters
interval
Dead interval in seconds. Valid values range from 3 through 65535 seconds. The default is 40.
Modes

Interface subtype configuration mode

Usage Guidelines

If you change the dead interval, the hello interval is automatically changed to a value that is one fourth that of the new dead interval, unless the hello interval is also explicitly configured using the ip ospf hello-interval command.

The recommended setting is that:

  • The dead interval is four times that of the hello interval.
  • The hello interval is ¼ times that of the dead interval.
  • If the OSPF hello interval and dead interval are set to more aggressive levels than 1:4 seconds respectively, the OSPF protocol might flap when the write memory command is used or in the case of any high CPU.

The running-config command displays only explicitly configured values of the hello interval, which means that a value that was automatically changed as the result of a dead-interval change is not displayed.

The no form of the command restores the default value.

Examples

The following example sets the dead interval to 200 on a specific OSPFv2 virtual Ethernet (VE) interface. 

device# configure terminal
device(config)# interface ve 1 
device(config-vif-1)# ip ospf dead-interval 200
History
Parent topic: Commands I