LevelOne GTL-2691 User Manual

Page 692

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20

| Unicast Routing

Configuring the Open Shortest Path First Protocol (Version 2)

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IP Address – Address of the interfaces assigned to a VLAN on the

Network Area (Add) page.
This parameter only applies to the Configure by Address page.

Cost – Sets the cost of sending a protocol packet on an interface,

where higher values indicate slower ports. (Range: 1-65535;

Default: 1)
The interface cost indicates the overhead required to send packets

across a certain interface. This is advertised as the link cost in router

link state advertisements.
Routes are assigned a metric equal to the sum of all metrics for each

interface link in the route.
This router uses a default cost of 1 for all ports. Therefore, if you install

a 10 Gigabit module, you need to reset the cost for all of the 1 Gbps

ports to a value greater than 1 to reflect the actual interface bandwidth.

Router Priority – Sets the interface priority for this router.

(Range: 0-255; Default: 1)
This priority determines the designated router (DR) and backup

designated router (BDR) for each OSPF area. The DR forms an active

adjacency to all other routers in the area to exchange routing topology

information. If for any reason the DR fails, the BDR takes over this role.
Set the priority to zero to prevent a router from being elected as a DR

or BDR. If set to any value other than zero, the router with the highest

priority becomes the DR and the router with the next highest priority

becomes the BDR. If two or more routers are set to the same highest

priority, the router with the higher ID will be elected.
If a DR already exists for an area when this interface comes up, the

new router will accept the current DR regardless of its own priority. The

DR will not change until the next time the election process is initiated.
Configure router priority for multi-access networks only and not for

point-to-point networks.

Hello Interval – Sets the interval between sending hello packets on an

interface. This interval must be set to the same value for all routers on

the network. (Range: 1-65535 seconds; Default: 10)
Hello packets are used to inform other routers that the sending router

is still active. Setting the hello interval to a smaller value can reduce

the delay in detecting topological changes, but will increase routing

traffic.

Dead Interval – Sets the interval at which hello packets are not seen

before neighbors declare the router down. This interval must be set to

the same value for all routers on the network. (Range: 1-65535

seconds; Default: 40, or 4 times the Hello Interval)
The dead-interval is advertised in the router's hello packets. It must be

a multiple of hello-interval and be the same for all routers on a specific

network.

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