Schneider Electric 840 USE 106 0 manual NOE Operating Modes and Hot Standby, Primary Mode

Ethernet Hot Standby Solution

NOE Operating Modes and Hot Standby

The NOE Modes The NOE modes are

Primary Mode

The Hot Standby state is primary, and all services are active.

Secondary Mode

The Hot Standby state is standby, and all server services are except DHCP.

Standalone Mode

Occurs when NOE is in a non redundant system, or if the CHS module is not

lpresent or is not healthy.

Offline Mode CPU is stopped.

CHS module is in Offline mode.

The Hot Standby and the NOE operating mode are synchronized by the conditions described in the following table.

CHS Module Status	HSBY State	NOE Operating Mode
Present and Healthy	Primary	Primary
Present and Healthy	Standby	Secondary
Present and Healthy	Offline	Offline
Present and Healthy	Unassigned	Standalone
Not present or unhealthy	N/A	Standalone

Any one of four events will affect the NOE operating mode. These four events occur when the NOE is powered-up, when an NOE executes a Hot Standby switchover, when an NOE goes to offline mode, or when a new application is downloaded to the NOE.

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