User's Guide

27
Bridge Function
The EM card bridges a packet from the EM1/EM2 port at the rear of the Blade Enclosure to the
internal network. It enables network communication between the management unit of the CPU blades
and switch modules in Blade Enclosure (e.g., EXPRESSSCOPE Engine) and the external devices.
TIPS:
When bridging, the EM card executes port filtering to prevent unnecessary packet from flowing in the
network.
The port number 49623 is used exclusively by EM card, and cannot be used in any other purposes.
SNMP Agent
SNMP is a protocol used to communicate the management data among network devices.
The administrator of the EM card can use SNMP to monitor the operating status of the EM card and
the blade system (Blade Enclosure, fan units, or power units) which the EM card manages.
Registering community name and SNMP trap message destination are to be specified in configuration
file.
DUPLEX EM
Installing two EM cards in the slots EM1 and EM2 enables duplex configuration. In the duplex
configuration, either of two EM cards works as an active EM to perform various features of the EM
card, and another one works as standby EM card. Two cards are connected with the internal serial
interface to transmit/receive information synchronously.
When an active EM fails or when the switchover command is executed, an active EM is changed to
standby EM after the system is rebooted. The standby EM is then works as an active EM.
IMPORTANT:
 In the duplex configuration, the revision of the EM firmware for EM card should be the same as
that in another EM card.
TIPS:
When switchover command is executed, the bridge feature is temporarily stopped, and the
management LAN interface may temporarily be disconnected.