Lan Control (Master Cm/Slave Cm); Figure 84 Lan Control (Switching Of The Master Cm) - Fujitsu ETERNUS AF S3 Series Design Manual

3. Connection Configuration
LAN Connection

LAN Control (Master CM/Slave CM)

This section explains how the LAN control controller of the ETERNUS AF operates.
Of the two controllers in the ETERNUS AF, the controller (CM) that is given the authority to manage the LAN is
called the Master CM and the CM that takes over the management when the Master CM fails is called the Slave
CM.
When an error occurs in the Master CM or LAN, the Master CM is switched automatically.
IP addresses of the LAN ports are not assigned to each CM. These IP addresses are assigned to the role of master
or slave. If the Master CM is switched, the same IP addresses are reused. Therefore, even if the Master CM is
switched and the physical port is changed, access can be maintained via the same IP addresses. The MAC
address is not inherited.
Figure 84 LAN Control (Switching of the Master CM)
IP address A
CM#0
has failed
ETERNUS AF
ETERNUS AF
Master CM
CM#0
Controller enclosure
The Master CM is switched.
Slave CM
IP address A
CM#0
Controller enclosure
When the Master CM is
switched, the IP addresses of
the previous Master CM are
taken over by the new
Master CM.
141
Slave CM
CM#1
Master CM
CM#1
Design Guide