3Com Switch 7754, Configuration Manual

Page: 707 / 940

Cluster Overview 707
The switch roles are switched according to the following rules:
Figure 183 Role switching roles
■
Each cluster has one (and only one) management device. A management
device collects NDP/NTDP information to discover and determine candidate
devices, which can be then added into the cluster through manual
configurations.
■
A candidate device becomes a member device after being added to a cluster.
Table 563 Switch roles in the cluster
Role Configuration Description
Management device
■
Configured with a public IP
address.
■
Receive management
commands that a user sends
through the public network
and process the received
commands
■
Provide management interfaces
for all switches in the cluster
■
Manage member devices by
redirecting commands, that is,
forward the commands to the
intended member devices for
processing
■
Provide the following
functions, including neighbor
discovery, topology
information collection, cluster
management, and cluster state
maintenance, and support all
types of FTP servers and SNMP
host proxies
Member device Normally, a member device is not
configured with a public IP
address
■
Member in the cluster
■
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
Candidate device
Member device
Management device
D
es
ig
nat
ed
as
a
m
anag
em
en
t d
ev
ic
e
Add
ed
to
a
clu
ste
r
R
em
ove
d fr
om
a
cl
ust
er
Re
m
ov
ed
fro
m
a
c
lu
ste
r