# npsend Check Mode

Specifies when the server is to provide confirmation upon receiving a `NON_PERSISTENT` message from a producer.

The npsend Check Mode property applies only to producers sending messages using `NON_PERSISTENT` delivery mode and non-transactional sessions.

Message confirmation has a great deal of impact on performance and should only be enabled when necessary. The circumstances in which a producer might want the server to send confirmation a `NON_PERSISTENT` message are:

- When Authorization is enabled, so the producer can take action if permission to send the message is denied by the server.
- When sending to a temporary destination, so the producer can take action if the message is sent to a temporary destination that has been destroyed.
- The message exceeded queue/topic limit (requires rejectIncoming policy for topics).
- Bridging of the message has failed.
- The server is out of memory or has encountered some other severe error.

The possible npsend Check Mode property modes are:

- default (no mode specified) - same behavior as in EMS 4.3 and prior. This means the server only provides confirmation of a `NON_PERSISTENT` message if authorization is enabled.
- always - the server always provides confirmation of a `NON_PERSISTENT` message.
- never - the server never provides confirmation of `NON_PERSISTENT` messages.
- temp_dest - the server provides confirmation of a `NON_PERSISTENT` message only when sending to a temporary destination.
- auth - the server provides confirmation of a `NON_PERSISTENT` message only if authorization was enabled when the connection was created.
- temp_auth - the server provides confirmation of a `NON_PERSISTENT` message if sending to a temporary destination or if authorization was enabled when the connection was created.

## Classic Configuration

The npsend check mode is set using the npsend_check_mode property in the tibemsd.conf file:

    npsend_check_mode = [always | never | temp_dest | auth | temp_auth]

## Administration Tool

This property cannot be set using the administration tool.

Copyright © Cloud Software Group, Inc. All rights reserved.