郵件流程與傳輸管線Mail flow and the transport pipeline

在 Exchange 伺服器上,郵件流程,就會發生通過傳輸管線。In Exchange Server, mail flow occurs through the transport pipeline. 傳輸管線是一群服務、 連線、 元件及共同運作來將所有郵件路由都傳送至組織內的 Exchange 信箱伺服器上的傳輸服務中之分類程式的佇列。The transport pipeline is a collection of services, connections, components, and queues that work together to route all messages to the categorizer in the Transport service on an Exchange Mailbox server inside the organization.

如需如何在新的 Exchange 2016 或 Exchange 2019 組織中設定郵件流程的詳細資訊,請參閱設定郵件流程和用戶端存取For information about how to configure mail flow in a new Exchange 2016 or Exchange 2019 organization, see Configure mail flow and client access.

了解傳輸管線Understanding the transport pipeline

傳輸管線是由下列服務所組成:The transport pipeline consists of the following services:

  • 信箱伺服器上的 front End Transport 服務: 這項服務會作為所有輸入與 (選擇性) 輸出外部 SMTP 流量的 Exchange Server 組織的無狀態 proxy。Front End Transport service on Mailbox servers: This service acts as a stateless proxy for all inbound and (optionally) outbound external SMTP traffic for the Exchange Server organization. 前端傳輸服務不會檢查郵件內容、不會與信箱傳輸服務通訊,且不會在本機將任何郵件排入佇列中。The Front End Transport service doesn't inspect message content, doesn't communicate with the Mailbox Transport service, and doesn't queue any messages locally.

  • 信箱伺服器上的傳輸服務: 這項服務是實際上等同於 Exchange Server 2010 中的 Hub Transport server role。Transport service on Mailbox servers: This service is virtually identical to the Hub Transport server role in Exchange Server 2010. 傳輸服務處理所有組織的 SMTP 郵件流程,執行郵件分類,並執行郵件內容檢查。The Transport service handles all SMTP mail flow for the organization, performs message categorization, and performs message content inspection. 與 Exchange 2010 中,不同的傳輸服務永遠不會進行通訊直接與信箱資料庫。Unlike Exchange 2010, the Transport service never communicates directly with mailbox databases. 這項工作現在是由 Mailbox Transport 服務來處理。That task is now handled by the Mailbox Transport service. 傳輸服務會在信箱傳輸服務、傳輸服務、前端傳輸服務與 Edge Transport Server 上的傳輸服務 (視您的組態而定) 之間路由傳送郵件。The Transport service routes messages among the Mailbox Transport service, the Transport service, the Front End Transport service, and (depending on your configuration) the Transport service on Edge Transport servers. 信箱伺服器上的傳輸服務將在本主題的後續內容中詳細說明。The Transport service on Mailbox servers is described in more detail later in this topic.

  • 信箱伺服器上的信箱傳輸服務: 這項服務是由兩項個別服務所組成:Mailbox Transport service on Mailbox servers: This service consists of two separate services:

    • 信箱傳輸提交服務: 這項服務連線至本機信箱資料庫使用 Exchange 遠端程序呼叫 (RPC) 來擷取郵件。Mailbox Transport Submission service: This service connects to the local mailbox database using an Exchange remote procedure call (RPC) to retrieve messages. 服務會透過 SMTP 將郵件提交給本機信箱伺服器或其他信箱伺服器上的傳輸服務。The service submits the messages over SMTP to the Transport service on the local Mailbox server or on other Mailbox servers. 信箱傳輸提交服務可存取與傳輸服務相同的路由拓撲資訊。The Mailbox Transport Submission service has access to the same routing topology information as the Transport service.

    • 信箱傳輸傳遞服務: 這項服務會從本機信箱伺服器上或其他信箱伺服器上的傳輸服務接收 SMTP 郵件,並連接至本機信箱資料庫使用 RPC 將郵件傳遞。Mailbox Transport Delivery service: This service receives SMTP messages from the Transport service on the local Mailbox server or on other Mailbox servers and connects to the local mailbox database using RPC to deliver the messages.

    信箱傳輸服務不會與其他信箱伺服器上的前端傳輸服務、信箱傳輸服務或信箱資料庫進行通訊。也不會將任何郵件排入佇列。The Mailbox Transport service doesn't communicate with the Front End Transport service, the Mailbox Transport service, or mailbox databases on other Mailbox servers. It also doesn't queue any messages locally.

  • Edge Transport server 上的傳輸服務: 這項服務是非常類似於信箱伺服器上的傳輸服務。Transport service on Edge Transport servers: This service is very similar to the Transport service on Mailbox servers. 如果您在周邊網路中安裝了 Edge Transport Server,所有來自網際網路或送出至網際網路的郵件,都將通過傳輸服務 Edge Transport Server。If you have an Edge Transport server installed in the perimeter network, all mail coming from the Internet or going to the Internet flows through the Transport service Edge Transport server. 此服務將在本主題的後續內容中詳細說明。This service is described in more detail later in this topic.

下圖顯示 Exchange 傳輸管線中元件之間的關係。The following diagram shows the relationships among the components in the Exchange transport pipeline.

注意

雖然本主題中的圖表顯示元件都在單一的 Exchange 伺服器上,在不同的 Exchange 伺服器上的這些元件間也會進行通訊。Although the diagrams in this topic show the components on a single Exchange server, communication also occurs between those components on different Exchange servers. 一律發生在本機 Exchange 伺服器的唯一通訊是信箱傳輸服務與本機信箱資料庫之間。The only communication that always occurs on the local Exchange server is between the Mailbox Transport service and the local mailbox database.

傳輸管線概觀圖表

來自外部寄件者的郵件如何進入傳輸管線How messages from external senders enter the transport pipeline

訊息從 Exchange 組織外部進入傳輸管線的方式取決於您是否已在周邊網路中部署已訂閱的 Edge Transport server。The way messages from outside the Exchange organization enter the transport pipeline depends on whether you have a subscribed Edge Transport server deployed in your perimeter network.

輸入郵件流程 (沒有 Edge Transport Server)Inbound mail flow (no Edge Transport servers)

下列圖表和清單將說明只有 Exchange Mailbox server 的輸入的郵件流程。The following diagram and list describe inbound mail flow with only Exchange Mailbox servers.

輸入的郵件流程間之傳輸管線中 (沒有 Edge Transport server)

  1. 來自組織外部的郵件進入傳輸管線透過預設接收連接器,名為 「 預設前端_<信箱伺服器名稱>_「 前端傳輸服務中。A message from outside the organization enters the transport pipeline through the default Receive connector named "Default Frontend <Mailbox server name>" in the Front End Transport service.

  2. 訊息會傳送至本機信箱伺服器或不同信箱伺服器上的傳輸服務。The message is sent to the Transport service on the local Mailbox server or on a different Mailbox server. 傳輸服務會接聽名為的預設接收連接器上郵件的 「 預設_<Mailbox server name>_」。The Transport service listens for messages on the default Receive connector named "Default <Mailbox server name>".

  3. 郵件會從傳輸服務傳送至本機信箱伺服器或不同信箱伺服器上的信箱傳輸傳遞服務。The message is sent from the Transport service to the Mailbox Transport Delivery service on the local Mailbox server or on a different Mailbox server.

  4. 接著,信箱傳輸傳遞服務會使用 RPC 將該郵件傳遞至本機信箱資料庫。The Mailbox Transport Delivery service uses RPC to deliver the message to the local mailbox database.

有 Edge Transport Server 的輸入郵件流程Inbound mail flow with Edge Transport servers

下列圖表和清單將說明已在周邊網路中安裝 Edge Transport Server 的輸入郵件流程The following diagram and list describe inbound mail flow with an Edge Transport server installed in the perimeter network

與 Edge Transport server 間之傳輸管線中的內送的郵件流程

  1. 來自 Exchange 組織外部的郵件進入傳輸管線透過預設接收連接器,名為 「 預設內部接收連接器_<Edge Transport server 名稱>_「 Edge Transport server 上的傳輸服務中。A message from outside the Exchange organization enters the transport pipeline through the default Receive connector named "Default internal Receive connector <Edge Transport server name>" in the Transport service on the Edge Transport server.

  2. 在 Edge Transport server 上傳輸服務中,預設的傳送連接器名為 「 EdgeSync-輸入到_<Active Directory 站台名稱>_」 將郵件傳送至已訂閱的 Active Directory 站台中的 Mailbox server。In the Transport service on the Edge Transport server, the default Send connector named "EdgeSync - Inbound to <Active Directory site name>" sends the message to a Mailbox server in the subscribed Active Directory site.

  3. 在信箱伺服器上前端傳輸服務中,預設接收連接器,名為 「 Default Frontend _ <Mailbox server name>_」 會接受郵件。In the Front End Transport service on the Mailbox server, the default Receive connector named "Default Frontend <Mailbox server name>" accepts the message.

  4. 訊息會從前端傳輸服務傳送至本機信箱伺服器或不同信箱伺服器上的傳輸服務。The message is sent from the Front End Transport service to the Transport service on the local Mailbox server or on a different Mailbox server. 傳輸服務會接聽名為的預設接收連接器上郵件的 「 預設_<Mailbox server name>_」。The Transport service listens for messages on the default Receive connector named "Default <Mailbox server name>".

  5. 郵件會從傳輸服務傳送至本機信箱伺服器或不同信箱伺服器上信箱傳輸傳遞服務。The message is sent from the Transport service to the Mailbox Transport Delivery service on the local Mailbox server, or on a different Mailbox server.

  6. 接著,信箱傳輸傳遞服務會使用 RPC 將該郵件傳遞至本機信箱資料庫。The Mailbox Transport Delivery service uses RPC to deliver the message to the local mailbox database.

來自內部寄件者的郵件如何進入傳輸管線How messages from internal senders enter the transport pipeline

來自組織內部的 SMTP 郵件會以下列其中一種方式透過信箱伺服器上的傳輸服務進入傳輸管線:SMTP messages from inside the organization enter the transport pipeline through the Transport service on a Mailbox server in one of the following ways:

  • 透過接收連接器。Through a Receive connector.

  • 從收取目錄或重新顯示目錄。From the Pickup directory or the Replay directory.

  • 從信箱傳輸提交服務。From the Mailbox Transport Submission service.

  • 透過代理程式提交。Through agent submission.

郵件會根據路由目的地或傳遞群組路由傳送。The message is routed based on the routing destination or delivery group.

輸出郵件流程 (沒有 Edge Transport Server)Outbound mail flow (no Edge Transport servers)

根據預設,在新的 Exchange Server 組織中,沒有設定將郵件傳送至網際網路的傳送連接器。By default, in a new Exchange Server organization, there's no Send connector that's configured to send messages to the Internet. 您必須自行建立傳送連接器。You need to create the Send connector yourself. 這麼做之後,就會出現下列圖表和清單中所述的輸出郵件流程。After you do that, Outbound mail flow occurs as described in the following diagram and list.

輸出郵件流程間之傳輸管線中 (沒有 Edge Transport server)

  1. 信箱傳輸提交服務會使用 RPC 從本機信箱資料庫擷取外寄郵件。The Mailbox Transport Submission service uses RPC to retrieve the outbound message from the local mailbox database.

  2. 信箱傳輸提交服務會使用 SMTP 將郵件傳送至本機信箱伺服器或不同信箱伺服器上的傳輸服務。The Mailbox Transport Submission service uses SMTP to send the message to the Transport service on the local Mailbox server or on a different Mailbox server.

  3. 在傳輸服務中,預設接收連接器,名為 「 預設_<Mailbox server name>_」 會接受郵件。In the Transport service, the default Receive connector named "Default <Mailbox server name>" accepts the message.

  4. 接下來的程序取決於傳送連接器的設定:What happens next depends on the configuration of the Send connector:

    • 預設值: 傳輸服務會使用您建立用來將郵件傳送至網際網路的傳送連接器。Default: The Transport service uses the Send connector you created to send the message to the Internet.

    • 輸出 proxy: 傳輸服務會使用您建立用來將郵件傳送至本機信箱伺服器或遠端信箱伺服器上的前端傳輸服務傳送連接器。Outbound proxy: The Transport service uses the Send connector you created to send the message to the Front End Transport service on the local Mailbox server or on a remote Mailbox server. 在前端傳輸服務中,預設接收連接器,名為 「 輸出 Proxy 前端_<Mailbox server name>_」 會接受郵件。In the Front End Transport service, the default Receive connector named "Outbound Proxy Frontend <Mailbox server name>" accepts the message. 前端傳輸服務會將郵件傳送至網際網路。The Front End Transport services sends the message to the Internet.

有 Edge Transport Server 的輸出郵件流程Outbound mail flow with Edge Transport servers

如果您已在周邊網路中安裝 Edge Transport Server,則外寄郵件永遠不會通過前端傳輸服務。If you have an Edge Transport server installed in the perimeter network, outbound mail never flows through the Front End Transport service. 有 Edge Transport Server 的輸出郵件流程如下列圖表與清單所示。Outbound mail flow with an Edge Transport server is described in the following diagram and list.

與 Edge Transport server 間之傳輸管線中的輸出郵件流程

  1. 信箱傳輸提交服務會使用 RPC 從本機信箱資料庫擷取外寄郵件。The Mailbox Transport Submission service uses RPC to retrieve the outbound message from the local mailbox database.

  2. 信箱傳輸提交服務會使用 SMTP 將郵件傳送至本機信箱伺服器或不同信箱伺服器上的傳輸服務。The Mailbox Transport Submission service uses SMTP to send the message to the Transport service on the local Mailbox server or on a different Mailbox server.

  3. 在 Active Directory 站台中的信箱伺服器上傳輸服務中,預設接收連接器,名為 「 預設_<Mailbox server name>_」 會接受郵件。In the Transport service on a Mailbox server in the subscribed Active Directory site, the default Receive connector named "Default <Mailbox server name>" accepts the message.

  4. 會將郵件傳送至 Edge Transport server 也會自動使用隱含和不可見的組織內傳送連接器傳送在相同組織中的 Exchange 伺服器之間的郵件。The message is sent to the Edge Transport server using the implicit and invisible intra-organization Send connector that automatically sends mail between Exchange servers in the same organization.

  5. 在 Edge Transport server 上傳輸服務中,預設接收連接器,名為 「 預設內部接收連接器_<Edge Transport server 名稱>_」 會接受郵件。In the Transport service on the Edge Transport server, the default Receive connector named "Default internal Receive connector <Edge Transport server name>" accepts the message.

  6. 在 Edge Transport server 上傳輸服務中,預設的傳送連接器名為 「 EdgeSync- _ <Active Directory 站台名稱>_ to Internet 」 將郵件傳送至網際網路。In the Transport service on the Edge Transport server, the default Send connector named "EdgeSync - <Active Directory site name> to Internet" sends the message to the Internet.

了解信箱伺服器上的傳輸服務Understanding the Transport service on Mailbox servers

每一封郵件已傳送或接收的 Exchange Server 組織中必須分類的信箱伺服器上的傳輸服務中,才能路由和傳遞。Every message that's sent or received in an Exchange Server organization must be categorized in the Transport service on a Mailbox server before it can be routed and delivered. 郵件被分類後,它就會處於傳遞到目的地信箱資料庫、 目的地資料庫可用性群組 (DAG)、 Active Directory 站台或 Active Directory 樹系中,或外部的目的地網域的傳遞佇列組織。After a message has been categorized, it's put in a delivery queue for delivery to the destination mailbox database, the destination database availability group (DAG), Active Directory site or Active Directory forest, or to the destination domain outside the organization.

信箱伺服器上的傳輸服務以下列元件及流程組成:The Transport service on a Mailbox server consists of the following components and processes:

  • SMTP 接收: 當傳輸服務接收郵件時,則會執行郵件內容檢查,並且如果已啟用,則執行反垃圾郵件檢查。SMTP Receive: When messages are received by the Transport service, message content inspection is performed and antispam inspection is performed if is enabled. SMTP 工作階段擁有一系列的事件,這些事件會先依特定的順序合作驗證郵件的內容,之後才會接受該郵件。The SMTP session has a series of events that work together in a specific order to validate the contents of a message before it's accepted. 郵件完全通過 SMTP 接收,而不拒絕之後被接收事件或反垃圾郵件代理程式,它就會處於提交佇列。After a message has passed completely through SMTP Receive and isn't rejected by receive events, or by an antispam agent, it's put in the Submission queue.

  • 提交: 提交是將郵件放到提交佇列的程序。Submission: Submission is the process of putting messages into the Submission queue. 分類程式會一次收取一封郵件並加以分類。The categorizer picks up one message at a time for categorization. 提交以三種方式進行:Submission happens in three ways:

    • 從「SMTP 接收」經由接收連接器。From SMTP Receive through a Receive connector.

    • 透過收取目錄或重新顯示目錄。這些目錄存在於信箱伺服器和 Edge Transport Server 上。複製到收取目錄或重新顯示目錄、且擁有正確格式的郵件檔案,會直接放到提交佇列中。Through the Pickup directory or the Replay directory. These directories exist on Mailbox servers and Edge Transport servers. Correctly formatted message files that are copied into the Pickup directory or the Replay directory are put directly into the Submission queue.

    • 透過傳輸代理程式。Through a transport agent.

  • 分類程式: 分類程式一次從提交佇列收取一封郵件。Categorizer: The categorizer picks up one message at a time from the Submission queue. 分類程式可完成以下步驟:The categorizer completes the following steps:

    • 收件者解析,包含頂層定址、通訊群組擴充和郵件複本發送。Recipient resolution, which includes top-level addressing, distribution group expansion, and message bifurcation.

    • 路由解析。Routing resolution.

    • 內容轉換。Content conversion.

      此外,會套用組織所定義的郵件流程規則。Additionally, mail flow rules that the organization defined are applied. 郵件被分類後,會根據郵件目的地被置於傳遞佇列。After messages have been categorized, they're put into a delivery queue that's based on the destination of the message. 郵件會進入佇列的目的地信箱資料庫、 DAG、 Active Directory 站台、 Active Directory 樹系或外部網域。Messages are queued by the destination mailbox database, DAG, Active Directory site, Active Directory forest, or external domain.

  • SMTP 傳送: 郵件從傳輸服務路由的方式取決於發生的位置相對的 Mailbox server 的郵件收件者的分類。SMTP Send: How messages are routed from the Transport service depends on the location of the message recipients relative to the Mailbox server where categorization occurred. 郵件可路由傳送至下列其中一個位置:The message could be routed to one of the following locations:

    • 傳送至相同信箱伺服器上的信箱傳輸傳遞服務。To the Mailbox Transport Delivery service on the same Mailbox server.

    • 傳送至屬於相同 DAG 之不同信箱伺服器上的信箱傳輸傳遞服務。To the Mailbox Transport Delivery service on a different Mailbox server that's part of the same DAG.

    • 至不同 DAG、 Active Directory 站台或 Active Directory 樹系中的信箱伺服器上傳輸服務。To the Transport service on a Mailbox server in a different DAG, Active Directory site, or Active Directory forest.

    • 透過下列方式傳送至網際網路:For delivery to the Internet through:

    • 同一個信箱伺服器上的傳送連接器。A Send connector on the same Mailbox server.

    • 不同信箱伺服器上的傳輸服務。The Transport service on a different Mailbox server.

    • 相同信箱伺服器或不同信箱伺服器上的前端傳輸服務 (如果已設定輸出 Proxy)。The Front End Transport service on the same Mailbox server or a different Mailbox server (if outbound proxy is configured).

    • 周邊網路中 Edge Transport Server 上的傳輸服務。The Transport service on an Edge Transport server in the perimeter network.

了解 Edge Transport Sever 上的傳輸服務Understanding the Transport service on Edge Transport servers

Edge Transport Server 上的傳輸服務元件等同於信箱伺服器上的傳輸服務元件。但在 Edge Transport Server 上的每個處理階段中實際執行的作業並不相同。下列清單會詳細說明其中的差異。The components of the Transport service on Edge Transport servers are identical to the components of the Transport service on Mailbox servers. However, what actually happens during each stage of processing on Edge Transport servers is different. The differences are described in the following list.

  • SMTP 接收: 當 Edge Transport server 訂閱至內部的 Active Directory 站台,名為的預設接收連接器 」 預設<Edge Transport server 名稱>」 會自動設定為接受來自內部 Mailbox server 及傳送自網際網路的郵件。SMTP Receive: When an Edge Transport server is subscribed to an internal Active Directory site, the default Receive connector named "Default <Edge Transport server name>" is automatically configured to accept mail from internal Mailbox servers and from the Internet. 網際網路郵件送達的 Edge Transport server,反垃圾郵件代理程式篩選連線和郵件內容,並協助您識別寄件者和收件者時要接受郵件至組織。When Internet messages arrive at the Edge Transport server, antispam agents filter connections and message contents and help identify the sender and the recipient while the message is being accepted into the organization. 反垃圾郵件代理程式會安裝,並預設為啟用。The antispam agents are installed and enabled by default. 此外也有附件篩選和連線篩選功能可供使用,但沒有內建的惡意程式碼篩選功能。Additional attachment filtering and connection filtering features are available, but built-in malware filtering is not. 此外,郵件流程規則 (也稱為傳輸規則) 皆 Edge 規則代理程式所控制。Also, mail flow rules (also known as transport rules) are controlled by the Edge Rule agent. 相較於信箱伺服器上的傳輸規則代理程式,只有一小部分的郵件流程規則條件可在 Edge Transport server 上。Compared to the Transport Rule agent on Mailbox servers, only a small subset of mail flow rule conditions are available on Edge Transport servers. 但是,有唯一的郵件流程規則動作是只能在 Edge Transport server 上使用的 SMTP 連線相關。But, there are unique mail flow rule actions related to SMTP connections that are available only on Edge Transport servers.

  • 提交: Edge Transport server 上,郵件通常進入提交佇列透過接收連接器。Submission: On an Edge Transport server, messages typically enter the Submission queue through a Receive connector. 但是,收取目錄和重新顯示目錄也可供使用。However, the Pickup directory and the Replay directory are also available.

  • 分類程式: 在 Edge Transport server 上,分類是簡短的處理程序中的郵件直接放入傳遞佇列中等待傳遞給內部或外部收件者。Categorizer: On an Edge Transport server, categorization is a short process in which the message is put directly into a delivery queue for delivery to internal or external recipients.

  • SMTP 傳送: 在 Edge Transport server 訂閱至內部 Active Directory 站台、 兩個傳送連接器會自動建立及設定。SMTP Send: When an Edge Transport server is subscribed to an internal Active Directory site, two Send connectors are automatically created and configured. 一個名為 「 EdgeSync- <Active Directory 站台名稱>to Internet 」 是負責將外寄郵件傳送給網際網路收件者;一個名為 「 EdgeSync-輸入至<Active Directory 站台名稱>"負責將輸入的郵件從網際網路傳送至內部收件者。One named "EdgeSync - <Active Directory site name> to Internet" is responsible for sending outbound mail to Internet recipients; the other named "EdgeSync - Inbound to <Active Directory site name>" is responsible for sending inbound mail from the Internet to internal recipients. 輸入的郵件會傳送至已訂閱的 Active Directory 站台中可用的信箱伺服器上的 Front End Transport 服務。Inbound mail is sent to the Front End Transport service on an available Mailbox server in the subscribed Active Directory site.