2-3
Role Configuration Function
Candidate device
Normally, a
candidate
device is not
assigned an
external IP
address
Candidate device refers to the devices
that do not belong to any clusters but are
cluster-capable.
Figure 2-2 illustrates the state machine of cluster role.
Candidate Switch
Designates as a
management switch
Member switchManagement switch
Cancels the
designated
Management
switch
Joins a
cluster
Leaves a
cluster
Figure 2-2 State machine of cluster role
z A candidate device becomes a management device when you create a cluster on
it. Note that a cluster must have one (and only one) management device. On
becoming a management device, the device collects network topology information
and tries to discover and determine candidate devices, which can then be added
to the cluster through configurations.
z A candidate device becomes a member device after being added to a cluster.
z A member device becomes a candidate device after it is removed from the cluster.
z A management device becomes a candidate device only after the cluster is
removed.
 Note:
After you create a cluster on an S3100 switch, the switch collects the network topology
information periodically and adds the candidate switches it finds to the cluster. The
interval for a management device to collect network topology information is determined
by the NTDP timer. If you do not want the candidate switches to be added to a cluster
automatically, you can set the topology collection interval to 0 by using the ntdp timer
command. In this case, the switch does not collect network topology information
periodically.