Configuring Ospf Interfaces - Cisco Catalyst 3550 series Software Configuration Manual

Configuring OSPF

Configuring OSPF Interfaces

You can use the ip ospf interface configuration commands to modify interface-specific OSPF
parameters. You are not required to modify any of these parameters, but some interface parameters (hello
interval, dead interval, and authentication key) must be consistent across all routers in an attached
network. If you modify these parameters, be sure all routers in the network have compatible values.
Note The ip ospf interface configuration commands are all optional.
Beginning in privileged EXEC mode, follow these steps to modify OSPF interface parameters:
Command
Step 1 configure terminal
Step 2
interface interface-id
Step 3
ip ospf cost
Step 4
ip ospf retransmit-interval seconds
Step 5
ip ospf transmit-delay seconds
Step 6
ip ospf priority number
Step 7
ip ospf hello-interval seconds
Step 8
ip ospf dead-interval seconds
Step 9
ip ospf authentication-key key
Step 10
ip ospf message digest-key keyid md5 key
Step 11 ip ospf database-filter all out
Step 12
end
Catalyst 3550 Multilayer Switch Software Configuration Guide
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Purpose
Enter global configuration mode.
Enter interface configuration mode, and specify the Layer 3 interface
to configure.
(Optional) Explicitly specify the cost of sending a packet on the
interface.
(Optional) Specify the number of seconds between link state
advertisement transmissions. The range is 1 to 65535 seconds. The
default is 5 seconds.
(Optional) Set the estimated number of seconds to wait before
sending a link state update packet. The range is 1 to 65535 seconds.
The default is 1 second.
(Optional) Set priority to help determine the OSPF designated router
for a network. The range is from 0 to 255. The default is 1.
(Optional) Set the number of seconds between hello packets sent on
an OSPF interface. The value must be the same for all nodes on a
network. The range is 1 to 65535 seconds. The default is 10 seconds.
(Optional) Set the number of seconds after the last device hello
packet was seen before its neighbors declare the OSPF router to be
down. The value must be the same for all nodes on a network. The
range is 1 to 65535 seconds. The default is 4 times the hello interval.
(Optional) Assign a password to be used by neighboring OSPF
routers. The password can be any string of keyboard-entered
characters up to 8 bytes in length. All neighboring routers on the
same network must have the same password to exchange OSPF
information.
(Optional) Enable MDS authentication.
• keyid—An identifier from 1 to 255.
• key—An alphanumeric password of up to 16 bytes.
(Optional) Block flooding of OSPF LSA packets to the interface. By
default, OSPF floods new LSAs over all interfaces in the same area,
except the interface on which the LSA arrives.
Return to privileged EXEC mode.
Chapter 31 Configuring IP Unicast Routing
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