Using The Area Id To Assign The Ospf Area Number; Attaching An Area To A Network - Lenovo RackSwitch G8264 Application Manual

Using the Area ID to Assign the OSPF Area Number

Attaching an Area to a Network

© Copyright Lenovo 2016
The OSPF area number is defined in the areaid <IP address> option. The octet
format is used to be compatible with two different systems of notation used by
other OSPF network vendors. There are two valid ways to designate an area ID:
 Single Number
Most common OSPF vendors express the area ID number as a single number.
For example, 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."
Multi‐octet (IP address): Placing the area number in the last octet (0.0.0.n)

Some OSPF vendors express the area ID number in multi‐octet format. For
example, "area 0.0.0.2" represents OSPF area 2 and can be specified directly
on the G8264 as "area­id 0.0.0.2".
On the G8264, using the last octet in the area ID, "area 1" is equivalent to
"area­id 0.0.0.1".
Note: Although both types of area ID formats are supported, be sure that the area
IDs are in the same format throughout an area.
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:
RS G8264(config)# interface ip <interface number>
RS G8264(config­ip­if)# ip ospf area <area index>
RS G8264(config­ip­if)# exit
For example, the following commands could be used to configure IP interface 14 to
use 10.10.10.1 on the 10.10.10.0/24 network, to define OSPF area 1, and to attach the
area to the network:
RS G8264(config)# router ospf
RS G8264(config­router­ospf)# area 1 area­id 0.0.0.1
RS G8264(config­router­ospf)# area 1 enable
RS G8264(config­router­ospf)# enable
RS G8264(config­router­ospf)# exit
RS G8264(config)# interface ip 14
RS G8264(config­ip­if)# ip address 10.10.10.1
RS G8264(config­ip­if)# ip netmask 255.255.255.0
RS G8264(config­ip­if)# enable
RS G8264(config­ip­if)# ip ospf area 1
RS G8264(config­ip­if)# ip ospf enable
Note: OSPFv2 supports IPv4 only. IPv6 is supported in OSPFv3 (see "OSPFv3
Implementation in Enterprise NOS" on page 578).
Chapter 35: Open Shortest Path First
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