Assigning the routing switch to OSPF areas
For more information, see
Assigning the routing switch to OSPF areas
on page 259.
Configuring an OSPF backbone or normal area
Syntax:
area [[
ospf-area-id
] | [backbone]] [normal] [[
ospf-area-id
] | [backbone]]
After using
router ospf
to globally enable OSPF and enter the global OSPF context, execute this command to
assign the routing switch to a backbone or other normal area.
The
no
form of the command removes the routing switch from the specified area.
Default: No areas; Range: 1 to16 areas (of all types)
ospf-area-id
Specifies a normal area to which you are assigning the routing switch. You can assign the routing switch to
one or more areas, depending on the area in which you want each configured VLAN or subnet to reside.
You can enter area IDs in either whole number or dotted decimal format. (The routing switch automatically
converts whole numbers to the dotted decimal format.)
For example, if you enter an area-ID of
1
, it appears in the switch's configuration as
0.0.0.1
and an area-ID
of 256 appears in the switch configuration as
0.0.1.0
.
An area ID can be a value selected to match the IP address of a VLAN belonging to the area or a value
corresponding to a numbering system you devise for the areas in a given autonomous system (AS.)
Entering an area ID of
0
or
0.0.0.0
automatically joins the routing switch to the backbone area.
The maximum area ID value is 255.255.255.254 (4,294,967,294.)
backbone
Assigns the routing switch to the backbone area and automatically assigns an area ID of
0.0.0.0
and an
area type of
normal
.
Using
0
or
0.0.0.0
with the above
ospf-area-id
option achieves the same result. The backbone area is
automatically configured as a
normal
area type.
Example
Chapter 11 Open Shortest Path First Protocol (OSPF)
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