Chapter 9: OSPF Configuration Guide
94
DIGITAL GIGAswitch/Router User Reference Manual
Creating Virtual Links
In OSPF, virtual links can be established:
•
To connect an area via a transit area to the backbone
•
To create a redundant backbone connection via another area
Each Area Border Router must be configured with the same virtual link. Note that virtual
links cannot be configured through a stub area.
To configure virtual links, enter the following commands in the Configure mode.
Configuring Autonomous System External (ASE) Link
Advertisements
These parameters specify the defaults used when importing OSPF AS External (ASE)
routes into the routing table and exporting routes from the routing table into OSPF ASEs.
To specify AS external link advertisements parameters, enter the following commands in
the Configure mode:
Create a virtual
link.
ospf add virtual-link
<number-or-string>
[neighbor
<IPaddr>
]
[transit-area
<area-num>
]
Set virtual link
parameters.
ospf set virtual-link
<number-or-string>
[state disable|enable] [cost
<num>
]
[retransmit-interval
<num>
] [transit-delay
<num>
]
[priority
<num>
] [hello-interval
<num>
]
[router-dead-interval
<num>
] [poll-interval
<num>
]
Specify the interval which AS
external link advertisements
will be generated and flooded
to an OSPF AS.
ospf set export-interval
<num>
Specify the number of AS
external link advertisements
which will be generated and
flooded to an OSPF AS.
ospf set export-limit
<num>
Specify AS external link
advertisement default
parameters.
ospf set ase-defaults [preference
<num>
]
[cost
<num>
] [type
<num>
]
[inherit-metric]