ProLiant BL p-Class GbE2 Interconnect Switch Application Guide

OSPF 116
For example, the following commands could be used to configure IP interface 14 for a presence on the
10.10.10.1/24 network, to define OSPF area 1, and to attach the area to the network:
>> # /cfg/l3/if 14 (Select menu for IP interface 14)
>> IP Interface 14# addr 10.10.10.1(Define IP address on
backbone
network)
>> IP Interface 14# mask 255.255.255.0(Define IP mask on
backbone)
>> IP Interface 14# ena (Enable IP interface 14)
>> IP Interface 14# ../ospf/aindex 1(Select menu for area index
1)
>> OSPF Area (index) 1 # areaid 0.0.0.1(Define area ID as OSPF
area 1)
>> OSPF Area (index) 1 # ena (Enable area index 1)
>> OSPF Area (index) 1 # ../if 14 (Select OSPF menu for
interface 14)
>> OSPF Interface 14# aindex 1 (Attach area to network on
interface 14)
>> OSPF Interface 14# enable (Enable interface 14 for area
index 1)
Interface cost
The OSPF link-state algorithm (Dijkstra’s algorithm) places each routing device at the root of a tree and
determines the cumulative cost required to reach each destination. Usually, the cost is inversely proportional to
the bandwidth of the interface. Low cost indicates high bandwidth. You can manually enter the cost for the output
route with the following command:
>> # /cfg/l3/ospf/if <OSPF interface number>/cost <cost value
(1-65535)>
Electing the designated router and backup
In any area with more than two routing devices, a Designated Router (DR) is elected as the central contact for
database exchanges among neighbors, and a Backup Designated Router (BDR) is elected in case the DR fails.
DR and BDR elections are made through the hello process. The election can be influenced by assigning a priority
value to the OSPF interfaces on the switch. The command is as follows:
>>#/cfg/l3/ospf/if <OSPF interface number>/prio <priority value
(0-255)>
A priority value of 255 is the highest, and 1 is the lowest. A priority value of 0 specifies that the interface cannot
be used as a DR or BDR. In case of a tie, the routing device with the lowest router ID wins.
Summarizing routes
Route summarization condenses routing information. Without summarization, each routing device in an OSPF
network would retain a route to every subnet in the network. With summarization, routing devices can reduce
some sets of routes to a single advertisement, reducing both the load on the routing device and the perceived
complexity of the network. The importance of route summarization increases with network size.
Summary routes can be defined for up to 16 IP address ranges using the following command:
>> # /cfg/l3/ospf/range <range number>/addr <IP address>/mask
<mask>
where <range number> is a number 1 to 16, <IP address> is the base IP address for the range, and <mask> is
the IP address mask for the range.