3Com Switch 4800G 24-Port Configuration Manual page 1078

1078 C 87: VRRP C
HAPTER
Principles of VRRP
ONFIGURATION
IPv6-based VRRP packet format
Figure 321 IPv6-based VRRP packet format
0 3
Version Type
Auth Type
As shown in Figure 321, an IPv6-based VRRP packet consists of the following
fields:
Version: Version number of the protocol, 3 for VRRPv3.
■
Type: Type of the VRRP packet. Only one VRRP packet type is present, that is,
■
VRRP advertisement, which is represented by 1.
Virtual Rtr ID (VRID): Number of the virtual router, that is, number of the
■
standby group. It ranges from 1 to 255.
Priority: Priority of the switch in the standby group, in the range 0 to 255. A
■
greater value represents a higher priority.
Count IPv6 Addrs: Number of virtual IPv6 addresses for the standby group. A
■
standby group can have multiple virtual IPv6 addresses.
Auth Type: Authentication type. 0 means no authentication, 1 means simple
■
authentication. VRRPv3 does not support MD5 authentication.
Adver Int: Interval for sending advertisement packets, in centiseconds. The
■
default is 100.
Checksum: 16-bit checksum for validating the data in VRRPv3 packets.
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IPv6 Address: Virtual IPv6 address entry of the standby group. The allowed
■
number is given by the Count IPv6 Addrs field.
Authentication Data: Authentication key. Currently, this field is used only for
■
simple authentication and is 0 for any other authentication modes.
With VRRP enabled, the switches determine their respective roles in the
■
standby group by priority. The switch with the highest priority becomes the
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Virtual Rtr ID
Adver Int
IPv6 address 1
IPv6 address n
Authentication data 1
Authentication data 2
23
Priority Count IPv6 Addrs
Checksum
31