Use linux as an FTP server (3)

4. /etc/ftphosts
This file determines which hosts the user can enter from the system, while the other hosts are not allowed to enter. The format of each line is as follows:
command name < username> < addrglob>
where the command name is one of allow or deny, which allows the FTP user specified by username to be from the address specified by addrglob The server makes a connection; if it is deny, the FTP user specified by the username is denied to connect to the server from the address specified by addrglob. Here addrglob can list multiple addresses.

5. /etc/ftpconversions
This is the conversion file at the time of transfer. The format is:
<1>:<2>:<3>:<4>:<5>:<6>:<7>:<8>
The meaning of the item is as follows:
<1> is the prefix string to be deleted when the file is acquired;
<2> is the suffix string to be deleted when the file is acquired;
<3> is the prefix string to be inserted before the file name when the file is uploaded or downloaded;
<4> is added to the file name after an operation on the file is completed Suffix string;
<5> is used to specify the program that will be automatically run when a file is uploaded or downloaded;
<6> specifies some file types that can work on this file, each The types are separated by pipe characters. There are three types: T_REG, T_ASCII, and T_DIR, which represent ordinary files, ASCII files, and directories.
<7> There are three values: O_COMPRESS, O_UNCOMPRESS, and O_TAR, respectively. To compress files, unzip files, or use the tar command.
<8> Describes what type of conversion is performed.

6. /var/log/xferlog
This is the FTP log file that stores all the records generated by the FTP server. Strictly speaking, it does not belong to the FTP configuration file.