Chapter 29
  |  IP Routing Commands
Open Shortest Path First (OSPFv3)
–  891  –
◆ Use the area default-cost command to specify the cost of a default summary 
route sent into a stub by an ABR attached to the stub area.
Example
This example creates a stub area 2, and makes it totally stubby by blocking all Type 
3 summary LSAs.
Console(config-router)#area 2 stub no-summary
Console(config-router)#
Related Commands
area default-cost (886)
area virtual-link This command defines a virtual link. To remove a virtual link, use the no form with 
no optional keywords. To restore the default value for an attribute, use the no form 
with the required keyword.vvvv
Syntax 
area area-id virtual-link router-id 
[dead-interval seconds] [hello-interval seconds] 
[retransmit-interval seconds] [transmit-delay seconds] 
no area area-id virtual-link router-id 
[dead-interval | hello-interval | retransmit-interval | transmit-delay] 
area-id - Identifies the transit area for the virtual link.The area ID can be in 
the form of an IPv4 address or as a four octet unsigned integer ranging 
from 0-4294967295.
router-id - Router ID of the virtual link neighbor. This specifies the Area 
Border Router (ABR) at the other end of the virtual link. To create a virtual 
link, enter this command for an ABR at both ends of the link. One of the 
ABRs must be next to the isolated area and the transit area at one end of 
the link, while the other ABR must be next to the transit area and backbone 
at the other end of the link.
dead-interval seconds - Specifies the time that neighbor routers will wait 
for a hello packet before they declare the router down. This value must be 
the same for all routers attached to an autonomous system. (Range: 1-
65535 seconds; Default: 4 x hello interval, or 40 seconds)
hello-interval seconds - Specifies the transmit delay between sending 
hello packets. Setting the hello interval to a smaller value can reduce the 
delay in detecting topological changes, but will increase the routing traffic. 
This value must be the same for all routers attached to an autonomous 
system. (Range: 1-65535 seconds; Default: 10 seconds)
retransmit-interval seconds - Specifies the interval at which the ABR 
retransmits link-state advertisements (LSA) over the virtual link. The 
retransmit interval should be set to a conservative value that provides an