在 Exchange 服务器上允许匿名中继Allow anonymous relay on Exchange servers

开放中继对于 Internet 上的邮件服务器而言是一个非常严重的问题。无意或有意配置为开放中继的邮件服务器允许通过开放中继服务器透明地重新路由来自任何源的邮件。这种行为掩盖了邮件的原始源,并使它看上去像是来自开放中继服务器的邮件。垃圾邮件发送者急切地寻找并使用开放中继服务器,因此请不要将邮件服务器配置为开放中继。Open relay is a very bad thing for messaging servers on the Internet. Messaging servers that are accidentally or intentionally configured as open relays allow mail from any source to be transparently re-routed through the open relay server. This behavior masks the original source of the messages, and makes it look like the mail originated from the open relay server. Open relay servers are eagerly sought out and used by spammers, so you never want your messaging servers to be configured for open relay.

另一方面,匿名中继是很常见的需求,因为许多公司拥有内部 Web 服务器、数据库服务器、监视应用程序,或生成电子邮件但无法真正发送这些邮件的其他网络设备。On the other hand, anonymous relay is a common requirement for many businesses that have internal web servers, database servers, monitoring applications, or other network devices that generate email messages, but are incapable of actually sending those messages.

在 Exchange Server 中,可以在邮箱服务器上的前端传输服务中创建一个专用的接收连接器,该连接器允许从特定的内部网络主机列表中进行匿名中继。In Exchange Server, you can create a dedicated Receive connector in the Front End Transport service on a Mailbox server that allows anonymous relay from a specific list of internal network hosts. 下面是有关匿名中继接收连接器的一些关键注意事项:Here are some key considerations for the anonymous relay Receive connector:

  • 您需要创建专用的接收连接器以指定允许匿名中继邮件的网络主机,以便阻止任何人或任何其他设备使用该连接器。You need to create a dedicated Receive connector to specify the network hosts that are allowed to anonymously relay messages, so you can exclude anyone or anything else from using the connector. 不要尝试将匿名中继功能添加到由 Exchange 创建的默认接收连接器。Don't attempt to add anonymous relay capability to the default Receive connectors that are created by Exchange. 限制对接收连接器的访问非常重要,因为您不想将该服务器配置为开放中继。Restricting access to the Receive connector is critical, because you don't want to configure the server as an open relay.

  • 需要在前端传输服务中创建专用的接收连接器,而不是在传输服务中进行创建。You need to create the dedicated Receive connector in the Front End Transport service, not in the Transport service. 在 Exchange Server 中,前端传输服务和传输服务在邮箱服务器上始终位于一起。In Exchange Server, the Front End Transport service and the Transport service are always located together on Mailbox servers. 前端传输服务具有一个名为 "默认前端_ <服务器名称> _ " 的默认接收连接器,该连接器配置为侦听来自 TCP 端口25上的任意源的入站 SMTP 连接。The Front End Transport service has a default Receive connector named Default Frontend <ServerName> that's configured to listen for inbound SMTP connections from any source on TCP port 25. 您可以在前端传输服务中创建另一个接收连接器,也用于在 TCP 端口 25 上侦听传入 SMTP 连接,但您需要指定允许使用该连接器的 IP 地址。You can create another Receive connector in the Front End Transport service that also listens for incoming SMTP connections on TCP port 25, but you need to specify the IP addresses that are allowed to use the connector. 专用的接收连接器将始终用于处理来自那些特定的网络主机的传入连接(配置为与正在连接服务器的 IP 地址最匹配的接收连接器胜出)。The dedicated Receive connector will always be used for incoming connections from those specific network hosts (the Receive connector that's configured with the most specific match to the connecting server's IP address wins).

    相比之下,传输服务具有一个名为 default _ <ServerName> _的默认接收连接器,该连接器也配置为列出来自任何源的入站 SMTP 连接,但此连接器侦听 TCP 端口2525,使其不与前端传输服务中的接收连接器发生冲突。In contrast, the Transport service has a Default receive connector named Default <ServerName> that's also configured to listed for inbound SMTP connections from any source, but this connector listens on TCP port 2525 so that it doesn't conflict with the Receive connector in the Front End Transport service. 此外,只有组织中的其他传输服务和 Exchange 服务器才应使用此接收连接器,因此将相应地设置身份验证和加密方法。Furthermore, only other transport services and Exchange servers in your organization are expected to use this Receive connector, so the authentication and encryption methods are set accordingly.

    有关详细信息,请参阅Mail flow and the transport pipeline安装过程中创建的默认接收连接器For more information, see Mail flow and the transport pipeline and Default Receive connectors created during setup.

  • 创建专用的接收连接器后,您需要修改其权限以允许仅由使用其 IP 地址标识的指定网络主机进行匿名中继。网络主机至少需要具有接收连接器的下列权限才能匿名中继邮件:After you create the dedicated Receive connector, you need to modify its permissions to allow anonymous relay only by the specified network hosts as identified by their IP addresses. At a minimum, the network hosts need the following permissions on the Receive connector to anonymously relay messages:

    • ms-Exch-Accept-Headers-Routing

    • ms-Exch-SMTP-Accept-Any-Recipient

    • ms-Exch-SMTP-Accept-Any-Sender

    • ms-Exch-SMTP-Accept-Authoritative-Domain-Sender

    • ms-Exch-SMTP-Submit

      有关接收连接器的权限的详细信息,请参阅接收连接器权限组接收连接器权限For more information about permissions on Receive connectors, see Receive connector permission groups and Receive connector permissions.

      有两种不同的方法可以用来配置在接收连接器上进行匿名中继所需的权限。下表介绍了这些方法。There are two different methods that you can use to configure the permissions that are required for anonymous relay on a Receive connector. These methods are described in the following table.

方法Method 授予的权限Permissions granted 优点Pros 缺点Cons
将 "匿名用户Anonymous)" 权限组添加到接收连接器,并Ms-Exch-SMTP-Accept-Any-Recipient将权限添加NT AUTHORITY\ANONYMOUS LOGON到接收连接器上的安全主体。Add the Anonymous users (Anonymous) permission group to the Receive connector and add the Ms-Exch-SMTP-Accept-Any-Recipient permission to the NT AUTHORITY\ANONYMOUS LOGON security principal on the Receive connector. 连接使用具有NT AUTHORITY\ANONYMOUS LOGON以下权限的安全主体:Connections use the NT AUTHORITY\ANONYMOUS LOGON security principal with the following permissions:
ms-Exch-Accept-Headers-Routing
ms-Exch-SMTP-Accept-Any-Recipient
ms-Exch-SMTP-Accept-Any-Sender
ms-Exch-SMTP-Accept-Authoritative-Domain-Sender
ms-Exch-SMTP-Submit
授予最小必需权限以允许匿名中继。Grants the minimum required permissions to allow anonymous relay. 更难配置(必须使用 Exchange 命令行管理程序)。More difficult to configure (must use the Exchange Management Shell).

网络主机被视为匿名发件人。The network hosts are considered anonymous senders. 邮件不会绕过反垃圾邮件或邮件大小限制检查,并且发件人的电子邮件地址无法解析为全局地址列表中对应的显示名称(如果有)。Messages don't bypass antispam or message size limit checks, and the sender's email address can't be resolved to the corresponding display name (if any) in the global address list.
Exchange 服务器ExchangeServers)权限组和外部安全ExternalAuthoritative)身份验证机制添加到接收连接器。Add the Exchange servers (ExchangeServers) permission group and the Externally secured (ExternalAuthoritative) authentication mechanism to the Receive connector. 连接使用具有MS Exchange\Externally Secured Servers以下权限的安全主体:Connections use the MS Exchange\Externally Secured Servers security principal with the following permissions:
ms-Exch-Accept-Headers-Routing
ms-Exch-Bypass-Anti-Spam
ms-Exch-Bypass-Message-Size-Limit
ms-Exch-SMTP-Accept-Any-Recipient
ms-Exch-SMTP-Accept-Any-Sender
ms-Exch-SMTP-Accept-Authentication-Flag
ms-Exch-SMTP-Accept-Authoritative-Domain-Sender
ms-Exch-SMTP-Accept-Exch50
ms-Exch-SMTP-Submit
更易于配置(可以在 Exchange 管理中心中执行所有操作)。Easier to configure (can do everything in the Exchange admin center).

网络主机被视为已经过身份验证的发件人。The network hosts are considered authenticated senders. 邮件绕过反垃圾邮件和邮件大小限制检查,发件人的电子邮件地址可以解析为全局地址列表中相应的显示名称。Messages bypass antispam and message size limit checks, and the sender's email address can be resolved to a corresponding display name in the global address list.
授予提交邮件的权限,就像是来自 Exchange 组织内的内部发件人。Grants the permissions to submit messages as if they originated from internal senders within your Exchange organization. 网络主机被视为完全可信,而不考虑卷、大小或它们所发送的邮件内容。The network hosts are considered completely trustworthy, regardless of the volume, size, or content of the messages that they send.

最后,您需要确定最符合贵组织需求的方法。我们将向您展示如何配置这两种方法。请记住要么采用这种方法,要么采用另一种方法,不能同时采用这两种方法。Ultimately, you need to decide on the approach that best fits the needs of your organization. We'll show you how to configure both methods. Just remember that it's one method or the other, and not both at the same time.

在开始之前,您需要知道什么?What do you need to know before you begin?

  • 估计完成该任务的时间:10 分钟。Estimated time to complete this task: 10 minutes.

  • 其中一些过程需要 Exchange 命令行管理程序。Some of these procedures require the Exchange Management Shell. 若要了解如何在本地 Exchange 组织中打开 Exchange 命令行管理程序,请参阅 Open the Exchange Management ShellTo learn how to open the Exchange Management Shell in your on-premises Exchange organization, see Open the Exchange Management Shell.

  • 您必须先获得权限,然后才能执行此过程或多个过程。若要查看所需的权限,请参阅 邮件流权限主题中的"接收连接器"条目。You need to be assigned permissions before you can perform this procedure or procedures. To see what permissions you need, see the "Receive connectors" entry in the Mail flow permissions topic.

  • 若要了解本主题中的过程可能适用的键盘快捷键,请参阅 Exchange 管理中心内的键盘快捷键For information about keyboard shortcuts that may apply to the procedures in this topic, see Keyboard shortcuts in the Exchange admin center.

提示

遇到问题?请访问以下 Exchange 论坛寻求帮助:Exchange ServerExchange OnlineExchange Online ProtectionHaving problems? Ask for help in the Exchange forums. Visit the forums at: Exchange Server, Exchange Online, or Exchange Online Protection.

步骤 1:创建专用的接收连接器进行匿名中继Step 1: Create a dedicated Receive connector for anonymous relay

您可以在 EAC 或 Exchange 命令行管理程序中创建接收连接器。You can create the Receive connector in the EAC or in the Exchange Management Shell.

使用 EAC 创建专用的接收连接器进行匿名中继Use the EAC to create a dedicated Receive connector for anonymous relay

  1. 在 EAC 中,导航到 "邮件流 > 接收连接器",然后单击 "添加 " "添加" 图标In the EAC, navigate to Mail flow > Receive connectors, and then click Add Add icon. 此时将启动“新建接收连接器”**** 向导。This starts the New Receive connector wizard.

  2. 在第一页上,输入以下信息:On the first page, enter the following information:

    • 名称:输入接收连接器的描述性名称,例如,匿名中继。Name: Enter a descriptive name for the Receive connector, for example, Anonymous Relay.

    • 角色:选择 "前端传输"。Role: Select Frontend Transport.

    • 类型:选择 "自定义"。Type: Select Custom.

      完成后,单击“下一步”****。When you're finished, click Next.

  3. 在下一页上的“网络适配器绑定”**** 部分中,执行下列操作之一:On the next page, in the Network adapter bindings section, do one of the following:

    • 如果 Exchange 服务器具有一个网络适配器,而不使用不同的子网隔离内部和外部通信,则在端口25上接受现有的 (所有可用的 IPv4) 条目。If the Exchange server has one network adapter, and doesn't segregate internal and external traffic by using different subnets, accept the existing (All available IPv4) entry on port 25.

    • 如果 Exchange 服务器具有内部网络适配器和外部网络适配器,并使用不同的子网 segregates 内部和外部网络流量,则可以通过限制连接器的使用来进一步增强连接器的安全性。源自内部网络适配器的请求。If the Exchange server has an internal network adapter and an external network adapter, and segregates internal and external network traffic by using different subnets, you can further enhance security for the connector by limiting the use of the connector to requests that originate on the internal network adapter. 若要执行此操作:To do this:

      1. 选择 "现有 (所有可用的 IPv4) " 条目**** ,单击 "删除删除图标",然后单击](../../media/ITPro_EAC_AddIcon.png)"添加 ![" "添加" 图标。Select the existing (All available IPv4) entry, click Remove Remove icon, and then click Add Add icon.

      2. 在生成的“网络适配器绑定”**** 对话框中,选择“指定 IPv4 地址或 IPv6 地址”**** 并输入一个在内部网络适配器上配置的有效可用的 IP 地址,然后单击“保存”****。In the resulting Network Adapter Bindings dialog, select Specify an IPv4 address or an IPv6 address, and enter a valid and available IP address that's configured on the internal network adapter, and then click Save.

    完成后,单击“下一步”****。When you're finished, click Next.

  4. 在下一页上的 "远程网络设置" 部分中,执行以下步骤:On the next page, in the Remote network settings section, do the following steps:

    1. 选择现有的 0.0.0.0-255.255.255.255条目,然后单击 "删除 删除图标",然后单击 "添加 ""添加" 图标。Select the existing 0.0.0.0-255.255.255.255 entry, and then click Remove Remove icon, and then click Add Add icon.

    2. 在生成的“远程地址设置”**** 对话框中,输入 IP 地址或 IP 地址范围,用来标识允许使用此连接器的网络主机,然后单击“保存”****。您可以重复此步骤以添加多个 IP 地址或 IP 地址范围。为了清楚地标识允许使用此连接器的网络主机,宁可标识得非常具体,也不能过于宽泛。In the resulting Remote Address Settings dialog, enter an IP address or IP address range that identifies the network hosts that are allowed use this connector, and then click Save. You can repeat this step to add multiple IP addresses or IP address ranges. Err on the side of being too specific instead of too general to clearly identify the network hosts that are allowed to use this connector.

    完成后,单击 "完成"。When you're finished, click Finish.

使用 Exchange 命令行管理程序为匿名中继创建专用的接收连接器Use the Exchange Management Shell to create a dedicated Receive connector for anonymous relay

若要在 Exchange 命令行管理程序中创建相同的接收连接器,请使用以下语法:To create the same Receive connector in the Exchange Management Shell, use the following syntax:

New-ReceiveConnector -Name <ConnectorName> -TransportRole FrontendTransport -Custom -Bindings <LocalIPAddresses>:25 -RemoteIpRanges <RemoteIPAddresses>

本示例将新建一个具有以下配置选项的接收连接器:This example creates a new Receive connector with the following configuration options:

  • 名称:匿名中继Name: Anonymous Relay

  • 传输角色FrontEndTransportTransport role: FrontEndTransport

  • 使用类型: CustomUsage type: Custom

  • 绑定0.0.0.0:25 (侦听在 TCP 端口25上的 Exchange server 中的所有网络适配器上配置的所有 IP 地址上的入站邮件。)Bindings: 0.0.0.0:25 (listen for inbound messages on all IP addresses that are configured on all network adapters in the Exchange server on TCP port 25.)

  • 允许使用此连接器的远程 IP 地址:192.168.5.10 和192.168.5.11Remote IP addresses that are allowed to use this connector: 192.168.5.10 and 192.168.5.11

New-ReceiveConnector -Name "Anonymous Relay" -TransportRole FrontendTransport -Custom -Bindings 0.0.0.0:25 -RemoteIpRanges 192.168.5.10,192.168.5.11

注意:Notes:

  • 在指定自定义使用类型时必须提供 Bindings 参数。The Bindings parameter is required when you specify the Custom usage type.

  • _RemoteIpRanges_参数接受单个 ip 地址、ip 地址范围(例如, 192.168.5.10-192.168.5.20)或无类别域间路由(CIDR)(例如192.168.5.1/24)。The RemoteIpRanges parameter accepts an individual IP address, an IP address range (for example, 192.168.5.10-192.168.5.20), or Classless InterDomain Routing (CIDR) (for example, 192.168.5.1/24). 可以指定用逗号分隔的多个值。You can specify multiple values separated by commas.

步骤 2:在专用的接收连接器上配置匿名中继权限Step 2: Configure the permissions for anonymous relay on the dedicated Receive connector

在简介中所述,有两种不同的方法可用于配置接收连接器所需的权限:As described in the introduction, there are two different methods you can use to configure the required permissions on the Receive connector:

  • 将连接配置为匿名。Configure the connections as anonymous.

  • 将连接配置为外部安全。Configure the connections as externally secured.

选择一种方法或另一种方法。Choose one method or the other. 这些示例使用您在步骤 1 中创建的名为匿名中继的接收连接器。The examples use the Receive connector named Anonymous Relay that you created in Step 1.

将连接配置为匿名Configure the connections as anonymous

在 Exchange 命令行管理程序中运行以下命令:Run the following commands in the Exchange Management Shell:

1.

Set-ReceiveConnector "Anonymous Relay" -PermissionGroups AnonymousUsers
Get-ReceiveConnector "Anonymous Relay" | Add-ADPermission -User "NT AUTHORITY\ANONYMOUS LOGON" -ExtendedRights "Ms-Exch-SMTP-Accept-Any-Recipient"

将连接配置为外部安全Configure the connections as externally secured

  1. 在 EAC 中,导航到 "邮件流 > 接收连接器",选择 "匿名中继" 连接器,然后单击 "](../../media/ITPro_EAC_EditIcon.png)编辑 ![编辑图标"。In the EAC, navigate to Mail flow > Receive connectors, select the Anonymous Relay connector, and then click Edit Edit icon.

  2. 在连接器属性中,单击“安全”**** 并进行以下选择:In the properties of the connector, click Security and make the following selections:

    • 身份验证:取消选择 "传输层安全性(TLS) " 并选择 "外部安全(例如,使用 IPsec)"Authentication: Deselect Transport Layer Security (TLS) and select Externally secured (for example, with IPsec).

    • 权限组:选择 " Exchange 服务器"。Permission groups: Select Exchange servers.

    完成后,单击“保存”****。When you're finished, click Save.

若要在 Exchange 命令行管理程序中执行这些相同的步骤,请运行以下命令:To perform these same steps in the Exchange Management Shell, run the following command:

Set-ReceiveConnector "Anonymous Relay" -AuthMechanism ExternalAuthoritative -PermissionGroups ExchangeServers

如何判断是否生效?How do you know this worked?

若要验证是否已成功配置匿名中继,请执行以下步骤:To verify that you've successfully configured anonymous relay, do the following steps:

  • 验证专用的接收连接器的配置。Verify the configuration of the dedicated Receive connector.

    Get-ReceiveConnector "Anonymous Relay" | Format-List Enabled,TransportRole,Bindings,RemoteIPRanges
    
  • 验证专用的接收连接器的权限。Verify the permissions on the dedicated Receive connector.

    Get-ADPermission "Anonymous Relay" -User "NT AUTHORITY\ANONYMOUS LOGON" | where {($_.Deny -eq $false) -and ($_.IsInherited -eq $false)} | Format-Table User,ExtendedRights
    

    Or

    Get-ADPermission "Anonymous Relay" -User "MS Exchange\Externally Secured Servers" | where {($_.Deny -eq $false) -and ($_.IsInherited -eq $false)} | Format-Table User,ExtendedRights
    
  • 使用 Telnet 测试一个或多个指定的网络主机能否连接到专用的接收连接器,以及能否通过连接器匿名中继邮件。Use Telnet to test if one or more of the specified network hosts can connect to the dedicated Receive connector, and can anonymously relay mail through the connector. 默认情况下,不会在大多数客户端或 Microsoft Windows 的服务器版本中安装 Telnet 客户端。By default, the Telnet Client isn't installed in most client or server versions of Microsoft Windows. 要安装它,请参阅 Install Telnet Client(安装 Telnet 客户端)。To install it, see Install Telnet Client.

    有关详细信息,请参阅使用 Telnet 测试 Exchange 服务器上的 SMTP 通信For more information, see Use Telnet to test SMTP communication on Exchange servers.

    如果网络主机是没有安装 Telnet 的设备,您可以暂时将一台计算机的 IP 地址添加到接收连接器,并在完成测试后,从接收连接器删除 IP 地址。If the network host is a device that doesn't have Telnet, you could temporarily add the IP address of a computer to the Receive connector, and then remove the IP address from the Receive connector when you're finished testing.

    对于测试,您将需要以下值:For the test, the you'll need the following values:

    • Destination:这是用于连接到专用接收连接器的 IP 地址或 FQDN。Destination: This is the IP address or FQDN that you use to connect to the dedicated Receive connector. 这可能是在其中定义接收连接器的邮箱服务器的 IP 地址。This is likely the IP address of the Mailbox server where the Receive connector is defined. 这与您在连接器上配置的“网络适配器绑定”**** 属性(或 Bindings 参数)值有关。This relates to the Network adapter bindings property (or the Bindings parameter) value that you configured on the connector. 您需要为环境使用有效值。You'll need to use the valid value for your environment. 在此示例中,我们将使用 10.1.1.1。In this example, we'll use 10.1.1.1.

    • 发件人的电子邮件地址:您可能会配置匿名中继邮件的服务器或设备,以使用组织的权威域中的发送电子邮件地址。Sender's email address: You'll probably configure the servers or devices that are anonymously relaying mail to use a sending email address that's in an authoritative domain for your organization. 在此示例中,我们将使用 chris@contoso.com。In this example, we'll use chris@contoso.com.

    • 收件人的电子邮件地址:使用有效的电子邮件地址。Recipient's email address: Use a valid email address. 在此示例中,我们将使用 kate@fabrikam.com。In this example, we'll use kate@fabrikam.com.

    • 邮件主题: TestMessage subject: Test

    • 邮件正文:这是一封测试邮件Message body: This is a test message

    1. 打开"命令提示符"窗口,键入 telnet,再按 Enter 键。Open a Command Prompt window, type telnet, and then press Enter.

    2. 键入 set localecho,再按 Enter 键。Type set localecho, and then press Enter.

    3. 键入 OPEN 10.1.1.1 25,再按 Enter 键。Type OPEN 10.1.1.1 25, and then press Enter.

    4. 键入 EHLO,再按 Enter 键。Type EHLO, and then press Enter.

    5. 键入 MAIL FROM:chris@contoso.com,再按 Enter 键。Type MAIL FROM:chris@contoso.com, and then press Enter.

    6. 键入 RCPT TO:kate@fabrikam.com,再按 ENTER 键。Type RCPT TO:kate@fabrikam.com, and then press Enter.

      • 如果收到响应250 2.1.5 Recipient OK,则接收连接器允许从网络主机匿名中继。If you receive the response 250 2.1.5 Recipient OK, the Receive connector allows anonymous relay from the network host. 继续执行下一步以完成测试邮件的发送。Continue to the next step to finish sending the test message.

      • 如果收到响应550 5.7.1 Unable to relay,则接收连接器不允许从网络主机进行匿名中继。If you receive the response 550 5.7.1 Unable to relay, the Receive connector doesn't allow anonymous relay from the network host. 如果发生这种情况,请执行以下操作:If this happens, do the following:

        • 请验证您连接的是专用接收连接器的正确 IP 地址或 FQDN。Verify that you're connecting to the correct IP address or FQDN for the dedicated Receive connector.

        • 请验证允许在其中运行 Telnet 的计算机使用接收连接器。Verify that the computer where you're running Telnet is allowed to use the Receive connector.

        • 请验证接收连接器的权限。Verify the permissions on the Receive connector.

    7. 键入 DATA,再按 Enter 键。Type DATA, and then press Enter.

      您应该会收到类似以下内容的响应:You should receive a response that looks like this:

      354 Start mail input; end with <CLRF>.<CLRF>

    8. 键入主题:测试,再按 Enter 键。Type Subject: Test, and then press Enter.

    9. 再次按 Enter 键。Press Enter again.

    10. 键入这是一封测试邮件,再按 Enter 键。Type This is a test message, and then press Enter.

    11. 按 Enter 键,键入句点 ( .Press Enter, type a period ( . ),再按 Enter 键。), and then press Enter.

      您应该会收到类似以下内容的响应:You should receive a response that looks like this:

      250 2.6.0 <GUID> Queued mail for delivery

    12. 若要与 SMTP 服务器断开连接,请键入 QUIT,再按 Enter 键。To disconnect from the SMTP server, type QUIT, and then press Enter.

      您应该会收到类似以下内容的响应:You should receive a response that looks like this:

      221 2.0.0 Service closing transmission channel

    13. 若要关闭 Telnet 会话,请键入 quit,再按 Enter 键。To close the Telnet session, type quit, and then press Enter.

  • 如果匿名中继间歇工作,您可能需要修改接收连接器的默认邮件发送速度和邮件限制。有关详细信息,请参阅接收连接器上的邮件限制If anonymous relay works intermittently, you may need to modify the default message rate and throttling limits on the Receive connector. For more information, see Message throttling on Receive connectors.