area range (OSPFv2)

Specifies area range parameters on an area border router (ABR).

Syntax

area { A.B.C.D | decimal } range E.F.G.H I.J.K.L advertise [ cost cost_value ]

area { A.B.C.D | decimal } range E.F.G.H I.J.K.L not-advertise [ cost cost_value ]

area { A.B.C.D | decimal } range E.F.G.H I.J.K.L cost cost_value

no area range

Parameters

A.B.C.D: Area address in IP address format.
decimal: Area address in decimal format.
E.F.G.H I.J.K.L: Specifies the IP address and mask portion of the range. All network addresses that match this network are summarized in one route and advertised by the ABR.
advertise: Sets the address range status to advertise and generates a Type 3 summary LSA.
cost cost_value: Sets the cost value for the area range. This value is used as the generated summary LSA cost. The range for cost_value is 1 to 6777214. If this value is not specified, the cost value is the default range metric calculation for the generated summary LSA cost.
not-advertise: Sets the address range status to DoNotAdvertise; the Type 3 LSA is suppressed, and the component networks remain hidden from other networks. This setting temporarily pauses the route summary from the area.

Modes

OSPF router configuration mode

OSPF router VRF configuration mode

Usage Guidelines

Use this command only on ABRs to specify a route summary for an existing area. The result is that one summary route is advertised to other areas by the ABR, in the form of a Type 3 LSA. Routing information is condensed at area boundaries and external to the area, and only one route is advertised for each address range.

For example, use this command is if you have many small networks advertised from area 0 to any other area, or from any non-backbone area into the backbone. This command gives you a summary route instead of many smaller routes. In an area, the OSPF database on each router must be an exact copy of the databases of the other routers. This means that no summary is allowed in the area.

The no form of the command disables the specification of range parameters on an ABR.

Examples

The following example advertises to Area 3 all the addresses on the network 10.1.1.0 255.255.255.0 in the ABR you are signed into.

device# configure terminal
device(config)# router ospf
device(config-router-ospf-vrf-default-vrf)# area 3 range 10.1.1.0 255.255.255.0 advertise