Transport logs in Exchange Server

Transport logs provide information about what's happening in the transport pipeline. For more information about the transport pipeline, see Mail flow and the transport pipeline.

The transport logs in Exchange Server are described in the following sections.

Agent logging

Agent logging records the actions that are performed on messages by specific antispam transport agents on the Exchange server. For more information, see these topics:

Enabled by default?: Yes

Default location of log files: Note that the folder isn't created until an agent attempts to write information to the log.

  • Mailbox servers:

    • Front End Transport service: %ExchangeInstallPath%TransportRoles\Logs\FrontEnd\AgentLog

    • Transport service: %ExchangeInstallPath%TransportRoles\Logs\Hub\AgentLog

  • Transport service on Edge Transport servers: %ExchangeInstallPath%TransportRoles\Logs\Edge\AgentLog

Connectivity logging

Connectivity logging records outbound message transmission activity by the transport services on the Exchange server. For more information, see these topics:

Enabled by default?: Yes

Default location of log files:

  • Mailbox servers:

    • Front End Transport service: %ExchangeInstallPath%TransportRoles\Logs\FrontEnd\Connectivity

    • Transport service: %ExchangeInstallPath%TransportRoles\Logs\Hub\Connectivity

    • Mailbox Transport Delivery service: %ExchangeInstallPath%TransportRoles\Logs\Mailbox\Connectivity\Delivery

    • Mailbox Transport Submission service:

  • Transport service on Edge Transport servers: %ExchangeInstallPath%TransportRoles\Logs\Edge\Connectivity

Message tracking and delivery reports for administrators

Message tracking is a detailed record of all message activity as mail flows through the transport pipeline on an Exchange server. For more information, see these topics:

Delivery reports for administrators is a targeted search of the message tracking log for messages that were sent to or from a specified mailbox. For more information, see these topics:

Enabled by default?: Yes

Default location of log files:

  • Mailbox servers: %ExchangeInstallPath%TransportRoles\Logs\MessageTracking:

    • MSGTRK files for the Transport service.

    • MSGTRMD files for the Mailbox Transport Delivery service.

    • MSGTRMS files for the Mailbox Transport Submission service.

  • Transport service on Edge Transport servers: %ExchangeInstallPath%TransportRoles\Logs\MessageTracking

Pipeline tracing

Pipeline tracing records snapshots of messages before and after the message is affected by transport agents in the transport pipeline. For more information, see these topics:

Enabled by default?: No

Default location of log files: Note that the folder isn't created until pipeline tracing is enabled.

  • Mailbox servers:

    • Transport service: %ExchangeInstallPath%TransportRoles\Logs\Hub\PipelineTracing

    • Mailbox Transport service: %ExchangeInstallPath%TransportRoles\Logs\Mailbox\PipelineTracing

  • Transport service on Edge Transport servers: %ExchangeInstallPath%TransportRoles\Logs\Edge\PipelineTracking

Protocol logging

Protocol logging records the SMTP conversations that occur on Send connectors and Receive connectors during message delivery. For more information, see these topics:

Enabled by default?: Only on these connectors:

  • The default Receive connector named Default Frontend <ServerName> in the Front End Transport service on Mailbox servers.

  • The implicit and invisible Send connector in the Front End Transport service on Mailbox servers.

For more information about these connectors, see Default Receive connectors created during setup and Implicit Send connectors.

Default location of log files:

  • Mailbox servers:

    • Front End Transport service:

    • Receive connectors: %ExchangeInstallPath%TransportRoles\Logs\FrontEnd\ProtocolLog\SmtpReceive

    • Send connectors: %ExchangeInstallPath%TransportRoles\Logs\FrontEnd\ProtocolLog\SmtpSend

    • Transport service:

    • Receive connectors: %ExchangeInstallPath%TransportRoles\Logs\Hub\ProtocolLog\SmtpReceive

    • Send connectors: %ExchangeInstallPath%TransportRoles\Logs\Hub\ProtocolLog\SmtpSend

    • Mailbox Transport Delivery service (Receive Connectors): %ExchangeInstallPath%TransportRoles\Logs\Mailbox\ProtocolLog\SmtpReceive\Delivery

    • Mailbox Transport Submission service:

    • Send connectors: %ExchangeInstallPath%TransportRoles\Logs\Mailbox\ProtocolLog\SmtpSend\Submission

    • Side effect messages: %ExchangeInstallPath%TransportRoles\Logs\Mailbox\ProtocolLog\SmtpSend\Delivery

  • Transport service on Edge Transport servers:

    • Receive connectors: %ExchangeInstallPath%TransportRoles\Logs\Edge\ProtocolLog\SmtpReceive

    • Send connectors: %ExchangeInstallPath%TransportRoles\Logs\Edge\ProtocolLog\SmtpSend

Routing table logging

Note: The Routing Log Viewer is no longer available in the Exchange Toolbox.

Routing table logging periodically records snapshots of the routing table that Exchange servers uses to deliver messages. For more information, see these topics:

Enabled by default?: Yes

Default location of log files:

  • Mailbox servers:

    • Front End Transport service: %ExchangeInstallPath%TransportRoles\Logs\FrontEnd\Routing

    • Transport service: %ExchangeInstallPath%TransportRoles\Logs\Hub\Routing

    • Mailbox Transport service:: %ExchangeInstallPath%TransportRoles\Logs\Mailbox\Routing:

    • MDRoutingConfig files for the Mailbox Transport Delivery service.

    • MSRoutingConfig files for the Mailbox Transport Submission service.

  • Transport service on Edge Transport servers: %ExchangeInstallPath%TransportRoles\Logs\Edge\Routing