What is the default value of the TTL in a VRRP advertisement?

A.
0 TTL

B.
1 TTL

C.
64 TTL

D.
255 TTL

Explanation:
Reference – RFC3768

5.2.2. Destination Address

The IP multicast address as assigned by the IANA for VRRP is: 224.0.0.18
This is a link local scope multicast address. Routers MUST NOT forward a datagram with this destination address regardless of its TTL.

5.2.3. TTL

The TTL MUST be set to 255. A VRRP router receiving a packet with the TTL not equal to 255 MUST discard the packet.
The priority value for the VRRP router that owns the IP address(es) associated with the virtual router MUST be 255 (decimal).

VRRP routers backing up a virtual router MUST use priority values between 1-254 (decimal). The default priority value for VRRP routers backing up a virtual router is 100 (decimal).

The priority value zero (0) has special meaning indicating that the current Master has stopped participating in VRRP. This is used to trigger Backup routers to quickly transition to Master without having to wait for the current Master to timeout.

7.1. Receiving VRRP Packets

Performed the following functions when a VRRP packet is received:

– MUST verify that the IP TTL is 255.
– MUST verify the VRRP version is 2.
– MUST verify that the received packet contains the complete VRRP
packet (including fixed fields, IP Address(es), and Authentication Data).
– MUST verify the VRRP checksum.
– MUST verify that the VRID is configured on the receiving interface and the local router is not the IP Address owner (Priority equals 255 (decimal)).
– MUST verify that the Auth Type matches the locally configured authentication method for the virtual router and perform that authentication method.

If any one of the above checks fails, the receiver MUST discard the packet, SHOULD log the event and MAY indicate via network management that an error occurred.

– MAY verify that “Count IP Addrs” and the list of IP Address matches the IP_Addresses configured for the VRID