serv-u| Server Serv-u: Fast build powerful FTP server
The rapid development of the Internet provides people with unprecedented information resources, and more and more people want to have their own online home when they enjoy the new experience brought by the Internet. In today's popular Internet applications, the number of WWW and FTP file transfer is the most popular. This article will combine serv-u this powerful, user-friendly, easy to learn and Easy-to-use FTP server software, detailed description of how in the shortest possible time to establish a complete FTP server. In addition to the specific installation and configuration instructions, the article will also involve some of the use of FTP to understand the relevant knowledge, hope to be able to help the vast number of netizens.
Brief introduction
Serv-u is currently one of the many FTP server software. By using Serv-u, users can set up any PC as an FTP server so that users or other consumers can use the FTP protocol to connect to the FTP server through any PC on the same network, to copy, move, create, and delete files or directories. The FTP protocol mentioned here is specifically used to specify the standards and rules for file transfer between computers, just because there is a special protocol such as FTP, so that people can use different types of computers, different types of operating systems, different types of files to communicate with each other.
Although the current FTP server-side software variety, each have advantages, but serv-u by virtue of its unique function to expose the head. Specifically, Serv-u can provide the following features:
Windows-compliant user interface is friendly and easy to master.
Supports real-time multi-user connections, supports anonymous user access, and ensures PC uptime by limiting the maximum number of user visits at the same time.
Security can be outstanding. Security precautions can be set at both the directory and file levels. can provide different settings for different users, support the group to manage a large number of users. You can grant or deny access to users based on IP.
Support for file upload and download of breakpoints in the process of continuous transmission.
Multiple-homed sites with multiple IP addresses are supported.
can set the ratio of upload and download, hard disk space quota, network use bandwidth, etc., so that the user limited resources can not be consumed by a large number of FTP access users.
Can be run as a system service background.
Can be used to set the user login or exit when the display information, support for the Unix-style external links.
Listed above are just a serv-u of a number of functions, the specific use will be detailed in the next article, here to illustrate the point, serv-u in the maintenance of a comprehensive, powerful foundation, provide a completely easy-to-use interface, you can say that everything in control.
Instructions for use
All of the setup issues that users may encounter during the use of Serv-u can be implemented through the menu options in the Serv-u window. If the user after installing Serv-u, start serv-u, the screen does not show the Serv-u control window, you can right-click in the taskbar system tray serv-u icon (a capital letter "U"), and then select the pop-up menu of the first "show window so that the Serv-u control window will be displayed on the screen.
Setting up an FTP server
The first item "Ftp-server" In the Setup menu in the Serv-u control window is used to set the FTP server overall. The first "FTP port number" in the window that appears after the selection is used to set the port numbers that the FTP server uses, and the FTP server will listen to all the visitors ' information through that port. In general, the FTP server's default port number is 21, but users can change freely according to their circumstances, as long as they can ensure that the port number used is not in conflict with other network applications. The point to note here is that using the server port that the user chooses is a good security precaution, and only the user and other users who know the port number can successfully connect to the server. Therefore, it is recommended that users use their own selected ports when setting up an FTP server, rather than simply using the default values.
The user then needs to set the maximum speed that the server can provide. In general, the user can empty this out, then the server will use all the possible bandwidth to provide services to customers. It is good to be able to provide maximum access to the user, but too many FTP users may eat up all the possible bandwidth, making other network applications almost impossible to implement. Therefore, it is important to have a reasonable control over the maximum bandwidth that the FTP server can occupy.
The next item is to set the maximum number of user visits allowed by the server. This allows users to limit the maximum number of FTP servers that can be accessed at the same time. If the entry is set to 0, the FTP server will deny any user access requirements, and if the item is vacated, Serv-u will not control the number of visitors until all system resources are exhausted. If users want their FTP servers to function properly, it is best to limit the number of visitors to the site. In general, even the older 486 machines, after using Serv-u, can provide access support for more than 20 users at the same time.
The first of a series of complex options after this is "start security features." If the user does not select the item, then anyone can access the FTP server directly through the network, and any files in the server are randomly copied, altered, or even deleted. In addition to those who have a small range of personal networks, do not want each login to repeat the user name, password and other tumultuous procedures, the user must ensure that the option has been selected, that is, the security of the server to start the function.
The next "ENCRYPT passwords" is automatically selected by default. In this way, Serv-u will use the same encryption mechanism as the UNIX operating system to encrypt and save the user's password. If the user does not choose to encrypt the password, all passwords entered by the user will be saved in plaintext in the Serv-u.ini file located in the Serv-u installation directory.
A subsequent entry is used to set whether anonymous access to the user input password is required. By default, the entry is blank so that users who use anonymous accounts to access the FTP server will not be required to enter a password. It is important to note that the detection of anonymous user passwords is very simple, as long as anonymous users enter any string that matches the format of the mail address, Serv-u will not further determine whether the e-mail address that the user entered is real.
The next step is to prevent the go-ahead. If the user chooses this option, Serv-u will adopt a new time billing approach, and those who want to prevent timeouts by periodically sending commands to the server will no longer succeed.
Subsequent options are used to set whether to delete files that do not have a full upload, if the user does not use the deletion function, then when a user uploads files to the FTP server in the process of error and did not realize the full file upload, Serv-u will be on the hard disk to retain the uploaded content, In order to achieve the upload file breakpoint continued transmission.
Here's what we're going to talk about across FTP attacks. Typically, when a file is transmitted using the FTP protocol, the client first issues a "port" command to the FTP server that contains the user's IP address and the port number that will be used for data transfer. After the server receives the command, it uses the user address information provided by the command to establish a connection with the user. In most cases, there is no problem with the above procedure, but when a client is a malicious user, the FTP server may be connected to other non-client machines by adding specific address information to the port command. Although the malicious user may not have the right to direct access to a particular machine, if the FTP server has access to the machine, then the malicious user, through the FTP server as an intermediary, will still be able to finally achieve the connection to the target server. This is what we refer to as cross server attacks. To prevent this from happening, users can select the "Prevent attacks across FTP servers" option so that Serv-u first verifies that the address information provided by the user is its true address before establishing a connection to any of the visitors. Everything is a two-way thing. We already know that using serv-u can prevent attacks across FTP servers, but we also give up the ability to transfer data between FTP servers and FTP servers. This is because the Serv-u only establishes a connection with those who provide the address that matches the actual address of the address provider, and the user will not be able to remotely control file transfers between two different FTP servers.
The last two options limit the maximum amount of time a user stays on an FTP server and specify the case of files and directory names on the server.
The other related options in this window are described in more detail later.
User account Management
One of the most basic tasks for users to use an FTP server is to add and manage user information. Open the Serv-u User Management window by selecting Users on the SETUP menu. The window can be divided into about two parts. The left window is used to display the users of all currently registered FTP servers. Select one of the users, and their detailed configuration information will be displayed on the right side of the window accordingly. If this is the first time you start Serv-u, only a system default account named "Default" will be displayed.
The following is a detailed description of the entire process of creating a new user account.
First click the NEW button at the far right of the window and enter the user name you want to create in the pop-up window that follows. The user name you enter appears in the User Name column to the right of the window. The user can also modify the name of the account established in this column.
The user can then enter the group name of the user group to which the account will belong or create a new group. The so-called group is the concept of people in order to facilitate the management of a large number of user groups introduced. We can divide a large number of individual users into different groups for unified management. Because users belonging to the same group have some common attributes, such as user password, root directory, etc., so users only need to individually set up individual accounts with special attributes, which greatly simplifies the management and maintenance of user accounts. It is important to note that the special user account "Anonymous" does not belong to any one user group.
In the subsequent password bar, you need to enter the password of the account number, if the user in the server's settings to select the Encryption password option (see above), then the password entered will automatically be stored in encrypted mode. The important point about the password is that only the first 8 characters of the input are valid, hoping to attract the attention of the vast serv-u users. In addition, if the user does not enter the corresponding password when creating the new account number, it does not mean that the user account does not have a password, serv-u will try to find out if the user account belongs to a user group and the user group has a uniform password. If Serv-u does not find the appropriate user group password, it will deny access to that user account. If the user really wants to not specify the password for an account, just enter "<>" in the password of the corresponding account number. An exception to this is the anonymous user account, which does not have a password, and serv-u only requires the user to enter any string that matches the format of the mail address.
In the "Home" column, set the FTP user's root directory, which is the home directory that the user automatically resides in after a successful logon. Each user account must have its own root directory, otherwise serv-u will deny access to that user account. Of course, if the account belongs to a group, and the user group has set a common root directory
