Nortel Networks WEB OS 212777 - Manual (Page 76)

Web OS 10.0 Application Guide
76 n Chapter 4: OSPF
212777-A, February 2002
Using the Area ID to Assign the OSPF Area Number
The OSPF area number is defined in the areaid <IP address> option. The octet format is
used in order to be compatible with two different systems of notation used by other OSPF net-
work vendors. There are two valid ways to designate an area ID:
n
Placing the area number in the last octet (0.0.0.n)
Most common OSPF vendors express the area ID number as a single number. For exam-
ple, the Cisco IOS-based router command “
network 1.1.1.0 0.0.0.255 area 1 ”
defines the area number simply as “ area 1. ” On the Web switch, using the last octet in
the area ID, “ area 1 ” is equivalent to “ areaid 0.0.0.1 ”.
n
Multi-octet (IP address)
Some OSPF vendors express the area ID number in multi-octet format. For example,
“
area 2.2.2.2 ” represents OSPF area 2 and can be specified directly on the Web
switch as “ areaid 2.2.2.2 ”.
N OTE – Although both types of area ID formats are supported, be sure that the area IDs are in
the same format throughout an area.
Attaching an Area to a Network
Once an OSPF area has been defined, it must be associated with a network. To attach the area
to a network, you must assign the OSPF area index to an IP interface that participates in the
area. The format for the command is as follows:
For example, the following commands could be used to configure IP interface 14 for a pres-
ence on the 10.10.10.1/24 network, to define OSPF area 1, and to attach the area to the net-
work:
>> # /cfg/ip/ospf/if <interface number> /aindex <area index>
>> # /cfg/ip/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)