Lantronix
SM12XPA Web User Guide
33848 Rev. A
Page
366
of
473
Interface Status
This page displays the OSPF6 interface status table. It is used to provide the OSPF6 interface status information.
Figure 21-2.4: OSPF6 Interface Status
Parameter Descriptions
:
Interface
: The Interface identification.
Interface Address
: The IPv6 network address.
Area ID
: The OSPF6 area ID.
Router ID
: The OSPF6 router ID.
State
: The state of the link.
DR ID
: The router ID of the DR (Designated Router). Each broadcast and NBMA network that has at least two
attached routers has a DR. The DR generates an LSA for the network and has other special responsibilities in the
running of the protocol. The DR is elected by the Hello Protocol.
If two or more routers are connected on a broadcast network and are configured for OSPF, they must
select a
DR
(Designated Router) and a
BDR
(Backup Designated Router). All routers in the broadcast
network must form an OSPF adjacency with all other routers. The goal of DR and BDR is to reduce the
complexity of the multi-access network from a link state database point-of-view. The DR/BDR act as
central points of exchanging link-state information instead of having to exchange info with all other
routers in the broadcast network (mesh). This reduces greatly the link-state database of routers.
Two factors influence DR/BDR election:
1)
Router ID: The Router ID is the highest IP address of the
device or the highest IP address among loopback addresses (if one is configured) on the Cisco router or
can be configured manually by “router-id a.b.c.d” command under the OSPF process.
2)
OSPF Priority:
This is by default 1 for all routers. The OSPF priority is configured per interface. The router with the
Highest OSPF Priority value will become the DR. If the priorities are the same (the default priority is 1 for
all routers), then the Router ID is the tie breaker. The router with the highest Router ID becomes the
DR
,
and the router with the next highest IP becomes the
BDR
.
BDR ID
: The router ID of the BDR (Backup Designated Router) as described above.
Pri
: The OSPF6 priority. It helps determine the DR and BDR on the network to which this interface is connected.
Cost
: The cost of the interface.
Hello
: Hello timer. A time interval that a router sends an OSPF6 hello packet.
Dead
: Dead timer. A time interval to wait before declaring a neighbor dead. The unit of measure is seconds.
Retransmit
: Retransmit timer. A time interval to wait before retransmitting a database description packet when
it has not been acknowledged.
