AR2200 can't establish VRRP with md5 authentication with Cisco router

Hello everyone,

I would like to share an interesting case i stumbled upon with you.

When trying to establish VRRP between a Cisco router and an AR2200 and implement MD5 authenticati, on the AR gives the following error:

Huawei VRRP/1/VRRPAUTHFAILED:OID 1.3.6.1.2.1.68.0.2 VRRP failed to authentication. (IPAddress=10.57.13.20, AuthErrorType=1)

Without authentication the VRRP works as intended.

Cause:

AuthErrorType=1 means the AR did not support the authentication type on the other side.

Cisco router encapsulates the packet with the wrong authentication type flag

From RFC 2338, the authentication type should be 0, 1, 2. md5 is IP Authentication Header, so Cisco should fill this as 2, not 254.

That's all for this case, If you have any problems or suggestions, please comment below.

Thanks.