Email is backing up on Exchange Server when using DLP

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Article ID: 165235

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Updated On:

Products

Data Loss Prevention Network Prevent for Email

Issue/Introduction

Data Loss Prevention Network Prevent for Email 

Email is processing very slow when using MS Exchange 2010 MTAs

Messages seen in RequestProcessor log:

[Severe] (SMTP_CONNECTION .5204] Peer disconnected unexpectedly...reason=End of stream

ReceivedTimeInMs=16 

MessageChainsTimeInMs=15

DotTimeInMs=30923

 

Cause

If an Exchange 2010 transport server receives messages from a previous version of Exchange Server or a non-Exchange source, Exchange attempts to achieve shadow redundancy by delaying the acknowledgement to the sending server until it verifies that the message has been successfully delivered to all next hops internally. 

The delayed acknowledgement time-out is controlled by the MaxAcknowledgementDelay attribute of each Receive connector. The default value is 30 seconds.

 

Review the DotTimeInMs for each message in the RequestProcessor log on the Email Prevent server. If it is close to 30000 Ms, then this may be the cause.

Environment

DLP Email Prevent is configured in Forwarding mode.

MS Exchange 2010 email server

MS Exchange Edge 2010 email gateway

Resolution

Setting the MaxAcknowledgementDelay attribute to 0 seconds and restarting the Exchange services removes the delay and messages are received immediately by the downstream MTA.