Usage Scenario
To improve the security of protocol packets, set an authentication key for VRRP Advertisement packets. You can run the vrrp vrid authentication-mode command to set an authentication mode and authentication key for a specified VRRP group.
Prerequisites
A VRRP group has been configured using the vrrp vrid command.
Configuration Impact
After you set an authentication key for a specified VRRP group, a backup device in the group compares its authentication key with the authentication key in a received VRRP Advertisement packet.
- If the authentication keys are the same, the backup device discards the packet and resets the timer after the VRRP module finishes processing.
- If the authentication keys are different, the backup device directly discards the packet and enters the Master state after a period that is three times the interval at which VRRP Advertisement packets are sent.
Precautions
- You must set the same authentication mode and authentication key for devices in a specified VRRP group. If you set different authentication modes or authentication keys, two master devices coexist. As a result, the VRRP group cannot work properly.
- If the MD5 algorithm is used for VRRP group authentication, a risk message is displayed. The HMAC-SHA256 algorithm is recommended.