Figure 41 Network diagram for a cluster
As shown in
function is the management switch, the other managed devices are member switches, and the device that
does not belong to any cluster but can be added to a cluster is a candidate switch. The management
switch and the member switches form the cluster.
Figure 42 Role change in a cluster
As shown in
A candidate switch becomes a management switch when you create a cluster on it. A management
switch becomes a candidate switch only after the cluster is removed.
A candidate switch becomes a member switch after being added to a cluster. A member switch
becomes a candidate switch after it is removed from the cluster.
How a cluster works
Cluster management is implemented through HW Group Management Protocol version 2 (HGMPv2),
which consists of the following protocols:
Neighbor Discovery Protocol (NDP)
Neighbor Topology Discovery Protocol (NTDP)
A cluster configures and manages the devices in it through the protocols. Cluster management involves
topology information collection and the establishment and maintenance of a cluster. Topology
information collection and cluster maintenance are independent from each other; in fact, topology
information collection starts before the cluster is created. The following workflow applies:
All devices use NDP to collect the information of directly connected neighbors, including their
software version, host name, MAC address and port number.
The management switch uses NTDP to do the following:
Collect the information of the devices within user-specified hops.
Collect the topology information of all devices.
Specify the candidate switches of the cluster based on the collected information.
41, the device configured with a public IP address and performing the management
42, a device in a cluster changes its role according to the following rules: