首先要确认您本地电脑的ftp客户端使用的是主动模式（Port）还是被动模式（PASV）。

如果本地电脑的ftp客户端为主动模式，需要确认您在服务器上开放了高端端口，并且在FTP Server中指定了这些端口。

如果本地电脑的ftp客户端使用的是被动模式，则需要您本地可开放相关端口用于数据交互（可关闭本地防火墙），但如果您的网络结构受限（如防火墙、路由限制），可能造成无法正常使用，出现频繁连接中断。

【原文链接：FTP上传经常中断 - 冬邦互联】

如果排除以上问题，请确认您本地的网络环境是否稳定，同时您的服务器带宽是否被占满；

如果排除以上问题，请确认在 ftp server 端（也就是服务器上）的“数据传输超时”的设置足够大：比如在 Linux 上使用 vsftp 时，需要修改 /etc/vsftpd/vsftpd.conf 文件里的 data_connection_timeout 参数。

在 Windows 系统里操作比较复杂：Overview

The <connections> element specifies the connection-related settings for FTP sites. More specifically, the settings in the <connections> element control the behavior for the FTP service with regard to how to manage clients that are connecting to an FTP site.

For example, the unauthenticatedTimeout, controlChannelTimeout, and dataChannelTimeout attributes specify the time-outs for an FTP site. The settings specify, respectively, when the FTP service will disconnect an FTP client that has not successfully logged in or is idle, or when to disconnect an idle data connection. Specifying values for the attributes in the <connections>element can directly affect the overall performance of your server by helping to police the number of active client sessions for your FTP sites.

Compatibility

Version

Notes

IIS 10.0

The <connections> element was not modified in IIS 10.0.

IIS 8.5

The <connections> element was not modified in IIS 8.5.

IIS 8.0

The <connections> element was not modified in IIS 8.0.

IIS 7.5

The <connections> element of the <ftpServer> element ships as a feature of IIS 7.5.

IIS 7.0

The <connections> element of the <ftpServer> element was introduced in FTP 7.0, which was a separate download for IIS 7.0.

IIS 6.0

N/A

Note

The FTP 7.0 and FTP 7.5 services shipped out-of-band for IIS 7.0, which required downloading and installing the modules from the following URL:

With Windows 7 and Windows Server 2008 R2, the FTP 7.5 service ships as a feature for IIS 7.5, so downloading the FTP service is no longer necessary.

Setup

To support FTP publishing for your Web server, you must install the FTP service. To do so, use the following steps.

Windows Server 2012 or Windows Server 2012 R2On the taskbar, click Server Manager.In Server Manager, click the Manage menu, and then click Add Roles and Features.In the Add Roles and Features wizard, click Next. Select the installation type and click Next. Select the destination server and click Next.On the Server Roles page, expand Web Server (IIS), and then select FTP Server.NoteTo support ASP.Membership authentication or IIS Manager authentication for the FTP service, you will need to select FTP Extensibility, in addition to FTP Service.

.Click Next, and then on the Select features page, click Next again.On the Confirm installation selections page, click Install.On the Results page, click Close.Windows 8 or Windows 8.1On the Start screen, move the pointer all the way to the lower left corner, right-click the Start button, and then click Control Panel.In Control Panel, click Programs and Features, and then click Turn Windows features on or off.Expand Internet Information Services, and then select FTP Server.NoteTo support ASP.Membership authentication or IIS Manager authentication for the FTP service, you will also need to select FTP Extensibility.Click OK.Click Close.Windows Server 2008 R2On the taskbar, click Start, point to Administrative Tools, and then click Server Manager.In the Server Manager hierarchy pane, expand Roles, and then click Web Server (IIS).In the Web Server (IIS) pane, scroll to the Role Services section, and then click Add Role Services.On the Select Role Services page of the Add Role Services Wizard, expand FTP Server.Select FTP Service.NoteTo support ASP.Membership authentication or IIS Manager authentication for the FTP service, you will also need to select FTP Extensibility.Click Next.On the Confirm Installation Selections page, click Install.On the Results page, click Close.Windows 7On the taskbar, click Start, and then click Control Panel.In Control Panel, click Programs and Features, and then click Turn Windows Features on or off.Expand Internet Information Services, and then FTP Server.Select FTP Service.NoteTo support ASP.Membership authentication or IIS Manager authentication for the FTP service, you will also need to select FTP Extensibility.Click OK.Windows Server 2008 or Windows VistaDownload the installation package from the following URL:Follow the instructions in the following walkthrough to install the FTP service:Installing and Troubleshooting FTP 7How ToHow to configure the default control and data channel time-outs for all FTP sitesOpen Internet Information Services (IIS) Manager:If you are using Windows Server 2012 or Windows Server 2012 R2:On the taskbar, click Server Manager, click Tools, and then click Internet Information Services (IIS) Manager.If you are using Windows 8 or Windows 8.1:Hold down the Windows key, press the letter X, and then click Control Panel.Click Administrative Tools, and then double-click Internet Information Services (IIS) Manager.If you are using Windows Server 2008 or Windows Server 2008 R2:On the taskbar, click Start, point to Administrative Tools, and then click Internet Information Services (IIS) Manager.If you are using Windows Vista or Windows 7:On the taskbar, click Start, and then click Control Panel.Double-click Administrative Tools, and then double-click Internet Information Services (IIS) Manager.In the Connections pane, click the server name, and then click the Sites node.In the Sites pane, click Set FTP Site Defaults... in the Actions pane.In the Advanced Settings dialog box, expand Connections, specify your time-outs in the Control Channel Timeoutand Data Channel Timeout fields, and then click OK.ConfigurationAttributes

Attribute

Description

controlChannelTimeout

Optional int attribute.

Specifies the timeout, in seconds, when a connection will be timed out because of inactivity on the control channel. Note: The FTP service will disconnect the session when this timeout is reached.

The default value is 120.

dataChannelTimeout

Optional int attribute.

Specifies the timeout, in seconds, when a connection will be timed out because of inactivity on the data channel. Note: The FTP service will only disconnect the data channel when this timeout is reached.

The default value is 30.

disableSocketPooling

Optional Boolean attribute. true if socket pooling is disabled; otherwise, false. The disableSocketPooling attribute specifies whether socket pooling is used for sites that are distinguished by IP address rather than port number or host name. If disableSocketPooling is set to false, then socket pooling is enabled and sockets are shared between sites that use the same socket number but different IP addresses. In this situation, the FTP service becomes the exclusive owner of the port on each address that is bound to the server. For example, if socket pooling is enabled on a server that has two IP addresses, 10.0.0.1 and 10.0.0.2, and an FTP site is bound to address 10.0.0.1 on port 21, the FTP service will also own port 21 on the 10.0.0.2 address. If disableSocketPooling is set to true, then there is no socket sharing for sites based on IP address. The default value is false.

maxBandwidth

Unused uint attribute.

Note: This attribute is not implemented for FTP 7.

maxConnections

Optional unit attribute.

Specifies the maximum number of simultaneous connections for an FTP site.

Note: Use the maxClientsMessage attribute of the <messages> element to specify a message that the FTP service will return to clients when the maximum number of simultaneous connections has been exceeded.

The default value is 4294967295 (unlimited.)

minBytesPerSecond

Optional int attribute.

Specifies the minimum bandwidth requirements for data transfers. Note: The FTP service will disconnect the data channel when the minimum bandwidth is not met.

The default value is 240.

resetOnMaxConnections

Optional Boolean attribute.

true if the FTP service should quickly disconnect an FTP session instead of sending a maximum connections response; otherwise false.

Note: The resetOnMaxConnections attribute optimizes the overhead when processing connections that are not allowed to connect because maxConnection limit was reached.

The default value is false.

serverListenBacklog

Optional int attribute.

Specifies the number of outstanding sockets that can be queued.

The default value is 60.

unauthenticatedTimeout

Optional int attribute.

Specifies the idle time-out, in seconds, between when a new connection is made and authentication succeeds. If the client does not successfully authenticate within the specified time period, the FTP service will disconnect the session.

The default value is 30.

Child Elements

None.

Configuration Sample

The following configuration sample displays an example <connections> element for a server that has the default control channel time-out set to 300 seconds.

<siteDefaults>   <ftpServer>      <connections controlChannelTimeout="300" />   </ftpServer></siteDefaults>

The following code samples illustrate how to set the default control channel time-out to 300 seconds..

AppCmd.exe

appcmd.exe set config -section:system.applicationHost/sites /siteDefaults.ftpServer.connections.controlChannelTimeout:"300" /commit:apphost

Note

You must be sure to set the commit parameter to apphost when you use AppCmd.exe to configure these settings. This commits the configuration settings to the appropriate location section in the ApplicationHost.config file.

C#

using System;using System.Text;using Microsoft.Web.Administration;internal static class Sample{   private static void Main()   {      using (ServerManager serverManager = new ServerManager())      {         Configuration config = serverManager.GetApplicationHostConfiguration();         ConfigurationSection sitesSection = config.GetSection("system.applicationHost/sites");         ConfigurationElement siteDefaultsElement = sitesSection.GetChildElement("siteDefaults");         ConfigurationElement ftpServerElement = siteDefaultsElement.GetChildElement("ftpServer");         ConfigurationElement connectionsElement = ftpServerElement.GetChildElement("connections");         connectionsElement["controlChannelTimeout"] = 300;         serverManager.CommitChanges();      }   }}

Imports SystemImports System.TextImports Microsoft.Web.AdministrationModule Sample   Sub Main()      Dim serverManager As ServerManager = New ServerManager      Dim config As Configuration = serverManager.GetApplicationHostConfiguration      Dim sitesSection As ConfigurationSection = config.GetSection("system.applicationHost/sites")      Dim siteDefaultsElement As ConfigurationElement = sitesSection.GetChildElement("siteDefaults")      Dim ftpServerElement As ConfigurationElement = siteDefaultsElement.GetChildElement("ftpServer")      Dim connectionsElement As ConfigurationElement = ftpServerElement.GetChildElement("connections")      connectionsElement("controlChannelTimeout") = 300      serverManager.CommitChanges()   End SubEnd Module

var adminManager = new ActiveXObject('Microsoft.ApplicationHost.WritableAdminManager');adminManager.CommitPath = "MACHINE/WEBROOT/APPHOST";var sitesSection = adminManager.GetAdminSection("system.applicationHost/sites", "MACHINE/WEBROOT/APPHOST");var siteDefaultsElement = sitesSection.ChildElements.Item("siteDefaults");var ftpServerElement = siteDefaultsElement.ChildElements.Item("ftpServer");var connectionsElement = ftpServerElement.ChildElements.Item("connections");connectionsElement.Properties.Item("controlChannelTimeout").Value = 300;adminManager.CommitChanges();

Set adminManager = createObject("Microsoft.ApplicationHost.WritableAdminManager")adminManager.CommitPath = "MACHINE/WEBROOT/APPHOST"Set sitesSection = adminManager.GetAdminSection("system.applicationHost/sites", "MACHINE/WEBROOT/APPHOST")Set siteDefaultsElement = sitesSection.ChildElements.Item("siteDefaults")Set ftpServerElement = siteDefaultsElement.ChildElements.Item("ftpServer")Set connectionsElement = ftpServerElement.ChildElements.Item("connections")connectionsElement.Properties.Item("controlChannelTimeout").Value = 300adminManager.CommitChanges()

如果超时的设置已经足够大，可以先测试本地网络的情况。如果排除了本地网络的问题，需要提交工单联系技术人员，并将测试本地网络的各种输出和结果一起上传到工单里。

【原文链接：FTP上传经常中断 - 冬邦互联】