3Com S7906E - Switch, Configuration Manual

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To do… Use the command… Remarks
Specify a cost for the default
route advertised to the NSSA
area
default-cost cost
Optional
Defaults to 1.
z
It is required to use the nssa command on all the routers attached to an NSSA area.
z
Using the default-cost command only takes effect on the ABR/ASBR of an NSSA area.
Configuring a Virtual Link
Non-backbone areas exchange routing information via the backbone area. Therefore, connectivity
between the backbone and non-backbone areas and within the backbone itself must be maintained.
If necessary physical links are not available for this connectivity maintenance, you can configure virtual
links to solve it.
Follow these steps to configure a virtual link:
To do… Use the command… Remarks
Enter system view system-view
—
Enter OSPF view
ospf [ process-id | router-id
router-id | vpn-instance
instance-name ] *
—
Enter area view area area-id —
Configure a virtual link
vlink-peer router-id [ hello
seconds | retransmit seconds |
trans-delay seconds | dead
seconds | simple [ plain |
cipher ] password | { md5 |
hmac-md5 } key-id [ plain |
cipher ] password ] *
Required
You need to configure this
command on both ends of a
virtual link.
Note that hello and dead
intervals must be identical on
both ends of the virtual link.
Configuring OSPF Network Types
OSPF classifies networks into four types: broadcast, NBMA, P2MP, and P2P, upon the link layer
protocol.
z
Broadcast: When the link layer protocol is Ethernet or FDDI, OSPF considers the network type as
broadcast by default.
z
NBMA: When the link layer protocol is Frame Relay, ATM or X.25, OSPF considers the network
type as NBMA by default.