Setting a Dead Time for a Neighbor Relationship

Procedure

1. Run system-view

   The system view is displayed.

2. Run interface interface-type interface-number

   The OSPF interface view is displayed.

3. (Optional) On an Ethernet interface, run undo portswitch

   The interface is switched to Layer 3 mode.

   By default, an Ethernet interface works in Layer 2 mode.

   

   Only the S5720-EI, S5720-HI, S5730-HI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-EI, S6720-HI, S6720S-EI, S6730-H, S6730S-H, S6730-S, and S6730S-S support switching between Layer 2 and Layer 3 modes.

4. Run ospf timer dead interval

   A dead time after which the neighbor relationship expires between two switches is set.

   By default, the dead time is 40s on a P2P or broadcast interface, and 120s on a P2MP or NBMA interface. The dead time is four times the interval for sending Hello packets on the same interface.

   

   A dead time longer than 20s is recommended. If the dead time is shorter than 20s, the OSPF neighbor relationship may be disconnected unexpectedly.

   Both the Hello timer (interval for sending Hello packets) and the Dead timer (interval after which a neighbor relationship expires) are restored to their default values upon a change of the network type.