Black Box LGB6026A, Management Manual

Page: 1154 / 1289

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C
HAPTER
47 | IP Routing Commands
Open Shortest Path First (OSPFv2)
C
OMMAND
U
SAGE
◆
All areas must be connected to a backbone area (0.0.0.0) to maintain
routing connectivity throughout the autonomous system. If it not
possible to physically connect an area to the backbone, you can use a
virtual link. A virtual link can provide a logical path to the backbone for
an isolated area, or can be configured as a backup connection that can
take over if the normal connection to the backbone fails.
◆
A virtual link can be configured between any two backbone routers that
have an interface to a common non-backbone area. The two routers
joined by a virtual link are treated as if they were connected by an
unnumbered point-to-point network.
◆
Any area disconnected from the backbone must include the transit area
ID and the router ID for a virtual link neighbor that is adjacent to the
backbone.
E
XAMPLE
This example creates a virtual link using the defaults for all optional
parameters.
Console(config-router)#network 10.4.0.0 0.255.255.0.0 area 10.4.0.0
Console(config-router)#area 10.4.0.0 virtual-link 10.4.3.254
Console(config-router)#
This example creates a virtual link using MD5 authentication.
Console(config-router)#network 10.4.0.0 0.255.255.0.0 area 10.4.0.0
Console(config-router)#area 10.4.0.0 virtual-link 10.4.3.254 message-digest-
key 5 md5 ld83jdpq
Console(config-router)#
R
ELATED
C
OMMANDS
show ip protocols ospf (1175)
network area
This command defines an OSPF area and the interfaces that operate within
this area. Use the
no form to disable OSPF for a specified interface.
S
YNTAX
[ no ] network ip-address netmask area area-id
ip-address - Address of the interfaces to add to the area.
netmask - Network mask of the address range to add to the area.
area-id - Area to which the specified address or range is assigned.
An OSPF area identifies a group of routers that share common
routing information. The area ID can be in the form of an IPv4
address or as a four octet unsigned integer ranging from
0-4294967295.