3Com Switch 4200G Configuration Guide

266 CHAPTER 32: CLUSTER CONFIGURATION
HGMP V2 provides the following functions:
■ Topology discovery: HGMP V2 implements NDP (neighbor discovery protocol) to
discover the information about the directly connected neighbor devices, including
device type, software/hardware version, connecting port and so on. The
information such as device ID, port mode (duplex or half duplex), product version,
and BootROM version can also be given.
■ Topology information collection: HGMP V2 implements NTDP (neighbor topology
discovery protocol) to collect the information about device connections and
candidate devices within a specified hop range.
■ Member recognition: A management device can locate and recognize the member
devices in the cluster and then deliver configuration and management commands
to them.
■ Member management: You can add a device to a cluster or remove a device from
a cluster on the management device. You can also configure management device
authentication and handshake interval for a member device on the management
device.
Cluster-related configurations are described in the following sections.
Cluster Roles According to their functions and status in a cluster, switches in the cluster play
different roles. You can specify the role a switch plays. A switch also changes its role
according to specific rules.
Following three cluster roles exist: management device, member device, and
candidate device.
Figure 84 shows the role changing rule.
Table 234 Cluster role
Role Configurations Functions
Management
device
■ Configured with a public
IP address.
■ Receiving management
commands from the
public network and
processing the received
commands
■ Providing management interfaces for all
switches in the cluster
■ Managing member devices by redirecting
commands
■ Forwarding commands to the intended
member devices
■ Neighbor discovery, topology information
collection, cluster management, cluster state
maintenance, and proxies
Member device Normally, a member device
is not configured with a
public IP address.
■ Cluster member
■ Neighbor discovery, being managed by the
management device, running commands
forwarded by proxies, and failure/log
reporting.
Candidate device Normally, a candidate device
is not configured with a
public IP address.
A candidate device is a switch that does not
belong to any cluster, although it can be added
to a cluster.