3Com 5500-EI Series, Reference Manual

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1-5
To protect unused sockets from being attacked by malicious users, the 3com switch 5500-EI provides
the following functions:
z
TCP 21 is enabled only when you start the FTP server.
z
TCP 21 is disabled after you shut down the FTP server.
Related commands: display ftp-server .
Examples
# Enable the FTP server.
<Sysname> system-view
System View: return to User View with Ctrl+Z.
[Sysname] ftp server enable
% Start FTP server
ftp timeout
Syntax
ftp timeout minutes
undo ftp timeout
View
System view
Parameters
minutes: Idle timeout time (in minutes), in the range 1 to 35791.
Description
Use the ftp timeout command to set the idle timeout time of an FTP client. When the idle time of the
FTP client exceeds this timeout time, the FTP server terminates the connection with the FTP client.
Use the undo ftp timeout command to restore the default idle timeout time.
By default, the idle timeout time is 30 minutes.
If an FTP connection between an FTP server and an FTP client breaks down abnormally, but the FTP
server cannot be aware of this, the FTP server will keep this connection. This will occupy system
resources and affect other FTP users’ log in. You can set an idle timeout time so that the FTP server
considers an FTP connection invalid and terminates it if no data exchange occurs on it in idle timeout
time.
Examples
# Set the idle timeout time to 36 minutes.
<Sysname> system-view
System View: return to User View with Ctrl+Z.
[Sysname] ftp timeout 36