Use Serv-U to create an FTP server)

Basic FTP knowledge

FTP is short for File Transfer Protocol (file transfer protocol), used to transfer files between two computers. The FTP protocol can work in two ways: Port and PASV. The Chinese meaning is active and passive.
The active connection process is that the client sends a connection request to the FTP port of the server (21 by default). The server accepts the connection and establishes a command link. When data needs to be transmitted, the server sends a connection request from Port 20 to the idle port of the client and establishes a data link to transmit data.
PASV (passive) connection process: the client sends a connection request to the FTP port of the server (21 by default). The server accepts the connection and establishes a command link. When data needs to be transmitted, the client sends a connection request to the idle port of the server and establishes a data link to transmit data.
Because the server actively connects to the client when data is transmitted by port, if the client is behind the firewall or NAT gateway, the file cannot be transmitted by port with the FTP server on the Internet. In this case, PASV is required. Almost all FTP client software supports these two methods. A special example is IE, which uses port by default. If you want to enable PASV in IE, open IE and choose tools> Internet Options> advanced from the menu, hook up before "use Passive FTP" (supported only by ie6.0 or above ).

How to install and set public network users and Intranet truehost users

Step 1,DownloadServ-U and install
If IIS is installed, disable the FTP server of IIs before configuring Serv-U:
Control Panel-> Administrative Tools-> services-> FTP Publishing Service, set the start type to manual, and then click STOP.
Serv-U is the most popular FTP server software on Windows. its official website is http://www.serv-u.com /. Can be downloaded from the official websiteAfter the download, use the default options for installation. After installation, start setting:

Step 2: Set Serv-U

Right-click "domains" and select "new domain" to add a new domain name.

Enter the IP address here. Generally, you do not need to enter it. leave it blank. Serv-U is bound to all IP addresses of the local machine, including dynamic IP addresses obtained from dial-up. Click "Next ".

Enter the domain name here. Click "Next ".

Enter the port number here. Use the default value 21. Click "Next ".

Select the storage location of the domain name. Use the default value. Click "finish ".

In this step, the domain name settings are complete. Note: If you use a public dynamic domain name using gateway port ing, select "Enable Dynamic DNS" here ".

Right-click users and select new user to add a new user.

Enter the user name here. Click "Next ".

Enter the password here. Click "Next ".

Enter the root directory of the user. Click "Next ".

Select whether to lock the user in the root directory. For security reasons, it is best to lock. After clicking "Next", the settings are complete and Serv-U can work properly.

By default, users can only download files. to grant more permissions to users, select the option in the red box on the right of the interface.

Step 3. Other settings of Serv-U
Anonymous Logon:
Open Serv-U, go to domains-> user.xxx.com-> Users, right-click a user, create a user, name it "anonymous", and configure the user's directory, you can log on to Serv-U anonymously.

Traffic limit:
Open Serv-U and enter domains-> user.xxx.com-> Users-> User Name,
Allow only () login (s) from same IP Address:
Number of connections allowed for the same IP address (only public network users and Intranet truehost users can use)
Max. upload speed
Maximum upload speed (Kbytes/s)
Max. download speed
Maximum download speed (Kbytes/s)
Max. No. of users
Maximum number of users

PASV Mode settings:
All FTP server software supports port mode. Most FTP server software supports port and PASV. Serv-U is supported in both modes by default. To disable the PASV mode, open Serv-U and go to domains-> user.xxx.com-> Settings-> advanced-> remove the hooks before "allow passive mode data transfers.
Users who use the Intranet Standard Edition cannot cancel the PASV method.

PASV mode and firewall problems:
If you have installed a firewall for the public network and Intranet truehost users, you need to open some ports on the firewall for use in PASV mode of FTP; otherwise, you cannot log on in PASV mode. In the local server-> Settings-> advanced-> PASV port range of Serv-U, enter the local port range used in PASV mode, for example, 60000-60020. If Windows 9x/me is used, set the port range to 5. If Windows NT/2000/XP/2003 is used, set the port range to 20. Then open the port range in the firewall.
Users who use the Intranet Standard Edition do not need to set this option.
Firewall settings
Note: Windows XP firewall automatically opens the PASV port for FTP. If you use Windows XP firewall, you do not need to set it.

Considerations for Public Network + port ing:
If you use a gateway port ing and a public dynamic domain name through the ADSL shared device, router, or other gateway to access the Internet, it is no problem to create an FTP server and use port to access the server. You must use PASV to access the server, you need to make the following settings:
1. In domains-> user.xxx.com, select Enable Dynamic DNS ". The "Dynamic DNS" option is displayed on the right ". Click "Dynamic DNS", enter the domain name "user.xxx.com" in "ip name", and leave "ip address" empty. Press F5 to obtain the IP address. Click "Apply" to save the settings.
2. Set the PASV port range, for example, 60000-60020, according to the above description in "PASV mode and firewall problems.
3. configure a Pasing for the PASV port on the gateway (ADSL shared device/router. For example, you can map port 60000-60020 of the gateway to port 60000-60020 of the local machine.

Ul/dl ratios (upload/download ratio) restrictions:
Ul/dl ratios is the limit on the upload/download ratio. If this function is set, you must upload a certain number of files before downloading the files. We recommend that you do not enable this function. If the file cannot be downloaded from your FTP site, this error occurs:
550 sorry, insufficient credit for download-Upload first
Remove uL/dl ratios restrictions in Serv-U. Setting Method: choose domains> user.xxx.com> Users> username> uL/dl ratios to cancel "enable upload/download ratios ". This function is disabled by default.

How to install and set the Intranet Standard Edition

Step 1. Install and set Serv-U
Installing Serv-U on the Intranet standard dynamic domain name website is more troublesome than the Internet. First, install and set Serv-U according to the above public network installation methods.
After setting, open the FTP client on the local machine, enter the server address 127.0.0.1, port 21, and connect to Serv-U. If you do not have the FTP client software, you can open IE and enter ftp: // 127.0.0.1/To see if you can log on. This step is very important. You must call Serv-U on the local machine to make the following settings. If the connection fails on the local machine, check whether the configuration process is correct and check whether the firewall is faulty. Some firewalls are strictly configured. By default, connections from the local IP address to the local IP address are blocked.

Step 2: Configure port ing
After the local machine passes through Serv-U, you can configure port ing. The configuration method is as follows:
1. log on to the kemai domain name management page.
2. Click "modify" on the right of the domain name to go to the "Modify domain name" page. The port ing interface is as follows:
Port 1: Port: 8881 port name:
Port 2: Port: 8882 port name:
Port 3: Port: 8883 port name:
Port 4: Port: 8884 port name:
Port 5: Port: 8885 port name:
3. In the modify table, select a port with an empty name. For example, if Port 1 is empty, write the upper-case port name "ftp" in the port name on the Right of Port 1 (you must write "ftp" instead of other names ). After filling in the port name, write down the port number. For example, the port number 1 in the above interface is "8881 ". Then press "Submit" to make the change take effect.
4. Start the internal network client software for the dynamic domain name of kemai, select File> Configuration> press "Next" three times to go to the "other information" window. The interface is as follows:

In the default settings, ftp port ing already exists. The port name is "ftp", the server address is "127.0.0.1", and the port number is "21 ". Use this default setting. Click "finish" and restart the service. In this step, the port ing configuration is complete.

Step 3: Test FTP
Open the FTP client, enter the Intranet domain name in the server address, for example, "username.xxx.com", and enter the port number "8881" in the port number to connect to the Intranet FTP. If used in IE, enter ftp://username.xxx.com: 8881 /. To use Intranet FTP in IE, You need to enable the PASV mode (refer to "FTP basics ").

Note:
1. Do not enable "Enable Dynamic DNS" on the Interface below Serv-U ".

2. The port name must be in uppercase "ftp ".
3. In the interface below the Intranet client, "Limit the maximum number of connections from the same IP address" refers to all TCP connections, and FTP requires two TCP links. To limit the number of connections, set the number of connections to a multiple of 2.

4. For the Intranet standard FTP website, PASV mode is required for normal use. For details about port mode and PASV mode, refer to the above "FTP basics ".
5. When you perform management and maintenance on your website or on the Intranet where the website is located, do not use the domain name as the server address. Try to use the Intranet IP address of the website computer instead, this avoids port ing and increases the speed. For example, if the IP address of your website is 192.168.0.1, write the server address as "192.168.0.1" on the FTP client and port as "21 ".