Reference Guide
Open Shortest Path First (OSPFv2 and OSPFv3) | 467
The OSPFv2 process evaluates the network commands in the order they are configured. Assign the
network address that is most explicit first to include all subnets of that address. For example, if you assign
the network address 10.0.0.0 /8, you cannot assign the network address 10.1.0.0 /16 since it is already
included in the first network address.
When configuring the
network command, you must configure a network address and mask that is a
superset of the IP subnet configured on the Layer-3 interface to be used for OSPFv2.
Use this command in CONFIGURATION ROUTER OSPF mode to set up each neighbor and OSPF area.
The Area can be assigned by a number or with an IP interface address.
Enable OSPFv2 on interfaces
Each interface must have OSPFv2 enabled on it. It must be configured for Layer 3 protocol, and not be
shutdown. OSPFv2 can also be assigned to a loopback interface as a virtual interface.
OSPF functions and features, such as MD5 Authentication, Grace Period, Authentication Wait Time, etc,
are assigned on a per interface basis.
Figure 24-9 presents an example of assigning an IP address to an interface and then assigning an OSPFv2
area that includes that Layer-3 interface’s IP address.
Figure 24-9. Configuring an OSPF Area Example
Dell Networking recommends that the OSPFv2 Router ID be the interface IP addresses for easier
management and troubleshooting.
Use the
show config command in CONFIGURATION ROUTER OSPF mode to view the configuration.
Command Syntax Command Mode Usage
network ip-address mask area area-id CONFIG-ROUTER-OSPF-id Enable OSPFv2 on an interface and
assign an network address range to a
specific OSPF area.
IP Address Format: A.B.C.D/M
Area ID Range: 0-65535 or A.B.C.D/M
Note: If using features like MD5 Authentication, ensure all the neighboring routers are also
configured for MD5.
FTOS#(conf)#int gi 4/44
FTOS(conf-if-gi-4/44)#ip address 10.10.10.10/24
FTOS(conf-if-gi-4/44)#no shutdown
FTOS(conf-if-gi-4/44)#ex
FTOS(conf)#router ospf 1
FTOS(conf-router_ospf-1)#network 1.2.3.4/24 area 0
FTOS(conf-router_ospf-1)#network 10.10.10.10/24 area 1
FTOS(conf-router_ospf-1)#network 20.20.20.20/24 area 2
FTOS(conf-router_ospf-1)#
FTOS#
Assign Layer-3 interface
with IP Address and
no shutdown
Assign interface’s
IP Address to an Area