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ip ospf message-digest-key
This command enables message-digest (MD5) authentication on the
specified interface and to assign a key-id and key to be used by neighboring
routers. Use the no form to remove an existing key.
Syntax
ip ospf message-digest-key key-id md5 key
no ip ospf message-digest-key key-id
• key-id - Index number of an MD5 key. (Range: 1-255)
• key - Alphanumeric password used to generate a 128 bit message
digest or “fingerprint.” (Range: 1-16 characters)
Command Mode
Interface Configuration (VLAN)
Default Setting
MD5 authentication is disabled.
Command Usage
• Normally, only one key is used per interface to generate authentication
information for outbound packets and to authenticate incoming packets.
Neighbor routers must use the same key identifier and key value.
• When changing to a new key, the router will send multiple copies of all
protocol messages, one with the old key and another with the new key.
Once all the neighboring routers start sending protocol messages back to
this router with the new key, the router will stop using the old key. This
rollover process gives the network administrator time to update all the
routers on the network without affecting the network connectivity. Once
all the network routers have been updated with the new key, the old key
should be removed for security reasons.
Example
This example sets a message-digest key identifier and password.
Console(config)#interface vlan 1
Console(config-if)#ip ospf message-digest-key 1 md5 aiebel
Console(config-if)#