Ip Gateway Redundancy; Healthcheck Mechanism - Motorola MOSCAD 68P02958C00-B User Manual

Remotely define SNMP and Motorola SSC parameters.
Erase the IP Interface/Gateway Flash memory and downloads a new system.

IP Gateway Redundancy

To minimize the risk of a SCADA control center single point of failure and to ensure high
availability for its applications, a redundant IP Gateway can be configured. When one
IP Gateway is not available, a second, redundant IP Gateway can be used. To increase the
availability of the LAN network, dual Ethernet segments can be used, and each IP Gateway
can be connected to a different segment.
In a redundant IP Gateway system configuration, one IP Gateway acts as the primary unit.
The primary IP Gateway communicates properly over MDLC communication and over the
SCADA channels. There is bi-directional transfer of both SCADA application messages and
IP Gateway management messages. The secondary IP Gateway transfers IP Gateway
management messages only. (It does not send or receive any MDLC messages, since it is
logically disconnected from the link.)

HealthCheck Mechanism

The IP Gateway system includes a HealthCheck mechanism which manages the MDLC
connectivity to the sites. Associated with each site are two links, through which the site can be
reached. A background mechanism in both the IP Gateway and the MOSCAD units constantly
verifies which links are available.
The HealthCheck mechanism uses the site table as the basis for its operations. As the
IP Gateway identifies which links are available, it can reduce communication overhead by
routing frames destined to sites through their operational links.
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System Overview