Quick Reference Guide

PowerConnect B-Series TI24X Configuration Guide 677
53-1002269-02
Configuring OSPF
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The area <ip-addr> | <num> parameter specifies the transit area.
The <router-id> parameter specifies the router ID of the OSPF router at the remote end of the
virtual link. To display the router ID on a Layer 3 Switch, enter the show ip command.
Refer to “Modify virtual link parameters” on page 677 for descriptions of the optional parameters.
Modify virtual link parameters
OSPF has some parameters that you can modify for virtual links. Notice that these are the same
parameters as the ones you can modify for physical interfaces.
You can modify default values for virtual links using the following CLI command at the OSPF router
level of the CLI, as shown in the following syntax.
Syntax: area <num> | <ip-addr> virtual-link <ip-addr> [authentication-key [0 | 1] <string>]
[dead-interval <num>]
[hello-interval <num>] [md5-authentication key-activation-wait-time <num> | key-id
<num> [0 | 1] key <string>]
[retransmit-interval <num>] [transmit-delay <num>]
The parameters are described below.
Virtual link parameter descriptions
You can modify the following virtual link interface parameters.
Authentication Key: This parameter allows you to assign different authentication methods on a
port-by-port basis. OSPF supports three methods of authentication for each interface—none,
simple password, and MD5. Only one method of authentication can be active on an interface at a
time.
The simple password method of authentication requires you to configure an alphanumeric
password on an interface. The password can be up to eight characters long. The simple password
setting takes effect immediately. All OSPF packets transmitted on the interface contain this
password. All OSPF packets received on the interface are checked for this password. If the
password is not present, the packet is dropped.
The MD5 method of authentication encrypts the authentication key you define. The authentication
is included in each OSPF packet transmitted.
MD5 Authentication Key: When simple authentication is enabled, the key is an alphanumeric
password of up to eight characters. When MD5 is enabled, the key is an alphanumeric password of
up to 16 characters that is later encrypted and included in each OSPF packet transmitted. You
must enter a password in this field when the system is configured to operate with either simple or
MD5 authentication.
MD5 Authentication Key ID: The Key ID is a number from 1 – 255 and identifies the MD5 key that
is being used. This parameter is required to differentiate among multiple keys defined on a router.
MD5 Authentication Wait Time: This parameter determines when a newly configured MD5
authentication key is valid. This parameter provides a graceful transition from one MD5 key to
another without disturbing the network. All new packets transmitted after the key activation wait
time interval use the newly configured MD5 Key. OSPF packets that contain the old MD5 key are
accepted for up to five minutes after the new MD5 key is in operation.