HP Jetdirect J7974E, Руководство администратора

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Using standard FTP, a control connection is opened by the client to the FTP server on the HP Jetdirect
print server. FTP control connections are used to exchange commands between the client and the FTP
server. The HP Jetdirect print server supports up to four control connections (or FTP sessions)
simultaneously. If the number of allowed connections is exceeded, a message indicating that service is
not available will be displayed.
FTP control connections use TCP port 21.
Data Connection
A second connection, a data connection, is created each time a file is transferred between the client
and the FTP server. The client controls the creation of a data connection by issuing the commands that
require a data connection (such as FTP
ls
,
dir
or
put
commands).
Although the
ls
and
dir
commands are always accepted, the HP Jetdirect FTP server supports a single
data connection for printing at a time.
The transmission mode for an FTP data connection with the HP Jetdirect print server is always in stream
mode, which marks the end-of-file by closing the data connection.
Once a data connection is established, the file transfer type (ASCII or binary) can be specified. Clients
may attempt to auto-negotiate a transfer type, and the default transfer type depends on the client system
(for example, UNIX may default to binary). To specify the transfer type, enter the
bin
or
ascii
command at the FTP prompt.
FTP Login
To start an FTP session, enter the following command from a MS-DOS or UNIX command prompt:
ftp <IP address>
where
<IP address>
is the valid IP address or node name configured for the HP Jetdirect print server.
See the figure below.
Figure B-1 FTP Login Example
154 Appendix B FTP Printing ENWW