Point-to-Point Support

You can manually configure the OSPF link type for a VLAN. The following table describes the link types.

OSPF Link Types

Link Type	Number of Routers	Description
Auto	Varies	ExtremeXOS automatically determines the OSPF link type based on the interface type. This is the default setting.
Broadcast	Any	Routers must elect a designated router (DR) and a backup designated router (BDR) during synchronization. Ethernet is an example of a broadcast link.
Point-to-point	Up to 2	This type synchronizes faster than a broadcast link because routers do not elect a DR or BDR. It does not operate with more than two routers on the same VLAN. The Point-to-Point Protocol (PPP) is an example of a point-to-point link. An OSPF point-to-point link supports only zero to two OSPF routers and does not elect a designated router (DR) or backup designated router (BDR). If you have three or more routers on the VLAN, OSPF fails to synchronize if the neighbor is not configured.
Passive		A passive link does not send or receive OSPF packets.

Note

The number of routers in an OSPF point-to-point link is determined per VLAN, not per link.

All routers in the VLAN must have the same OSPF link type. If there is a mismatch, OSPF attempts to operate, but it may not be reliable.

Published March 1, 2020prev | next