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Message Resend Logic

Introduction

The Message Resend Logic (MRL) feature determines how the CSP responds to unacknowledged messages.

Configuration

You can configure the following MRL options for all messages:

• Do Not Resend

• Resend Once *

• Resend Once and Generate Alarm

The CSP sends a General alarm of Unacknowledged Message to the host. The message includes the bytes of the message being resent.

Important! An unacknowledged Alarm message is resent, but it does not generate an additional Alarm message.

* The system default is Resend Once. In the case of an Matrix Controller switchover, the Message Resend Logic resets to Resend Once.

Critical Message Resend

If you wish to have specific critical messages resent until they are acknowledged by the host, enable the Resend Until Acknowledged (0x03) option. This option applies to the following messages:

• Alarm

• Alarm Cleared

• Request For Service

• Request For Service With Data

• Channel Released

This option helps to ensure that the host receives critical messages that, because of a host switchover for example, it may not have received initially. To enable Resend Until Acknowledged, you must also enable Resend Once.

RFS. A Status Message indicating that some entity is requesting service from the Excel platform.