dp(4)

NAME

dp − dedicated ports file, used by DDFA and DTC port ID

DESCRIPTION

The dp file has two uses:

DTC Port ID via Telnet
The dp file is used by the HP-UX telnet daemon (telnetd) to identify the calling port and board of a telnet connection from an HP Datacommunications and Terminal Controller (DTC)

At connection time, the host negotiates the telnet environment option, and the DTC replies with the port and board number of the connecting device. telnetd maps the port and board numbers to the well-known name for the device, which has previously been configured in the dp file.

DTC Device File Access (DDFA)
The dp file is used by the HP Datacommunications and Terminal Controller (DTC) Device File Access (DDFA) software to allow terminal server ports to be programatically accessed from HP-UX applications in the same way as devices connected directly to the HP-UX system. It contains a one-line entry for each configured DTC port.

The dp file contains the information the DDFA software needs to set up and manage a connection to a specified DTC port. The file is parsed by the Dedicated Port Parser (dpp) which spawns an outgoing connection daemon for each connection specified in the file.

Port ID via Telnet

To configure the dp file for use in port ID via telnet, the default file /etc/newconfig/ddfa/dp should be copied to a new file, and the copy configured with the appropriate values for the incoming connections. We recommend you create a directory /etc/ddfa to hold the dp file and the modified pcfs.

pcf information is in the following format:

dtc_ip_address board/port pseudonym

The exact details of each field are given in the Configuration Information section below.

DTC Outbound Connections

For DTC outbound connections, the following information is required:

dtc_ip_address board/port pseudonym config_file

The exact details of each field are given in the Configuration Information section below.

Configuration Information

There are three ways to specify the DTC port:

• Explicitly specify its IP address.

• Specify the IP address of the DTC then specify the port and board.

• Specify the IP address of the DTC and the TCP port service address of the port.

Comments can be appended by starting them with a # character; everything after the # is ignored by the parser. Fields are separated by space characters.

Refer to ddfa(7) for information about how to configure and install DDFA software.

The dp file has the following format:

dtc_ip_address This is the IP address of the DTC being accessed, or the IP address of the port on the DTC.

board/port This field contains the DTC board and port numbers, separated by the / character. It is not necessary to pad the values with leading zeros. The board and port numbers are not checked by dpp, but are checked by ocd. Valid values are 0 through 7 for board, and 0 through 31 for port (these restrictions do not apply if the TCP service port address is specified instead).

If the dtc_ip_address field explicitly defines the DTC port, the value in the port/board field must be xx/xx (use X or x).

If the entry is of the form xx/n where n is a decimal number, n is assumed to be the TCP port address, and this value is used when the connection is established. Otherwise, the destination is filled using the DTC formula:

(256×(32×board+port+1)+23)

pseudonym This is the absolute path and name of the device file known to the system and/or the end-user application. The device file name is limited to 14 characters. We recommend that the name reflect the connected device, and be similar to the pcf name, for example ocd_dtc1b1p1.

pc_file_path This is the path to the Port Configuration file (pcf) which contains the configuration information for the DTC port. This field is mandatory because the parser dpp uses the presence of this field as its flag to spawn a daemon for the line. We recommend that the name of the file reflect the connected device, and be similar to the pcf name, for example pcf_dtc1b1p1.

EXAMPLES

The following examples illustrate file entry syntax.

A printer is connected to port 1 of board 3 of a DTC with the IP address 11.234.87.123. The device attached to the port can be accessed with the HP-UX spooler by using the device file /dev/ocd_1p1 in the lpadmin command. The port is to be profiled using data in the file /etc/ddfa/pcf_lp1:

11.234.87.123 03/01 /dev/ocd_lp1 /etc/ddfa/pcf_lp1 # lp1 b1,n2,f7

Consider a printer connected to the DTC port at IP address 11.234.87.124. The board/port field contains xx/xx. The file pcf_lp2 contains port profiling information:

11.234.87.124 xx/xx /dev/ocd_lp2 /etc/ddfa/pcf_lp2 # lp2 b2,n1

Specify a port using a TCP port address. The port address is calculated using the formula (256×(32×board+port+1)+23):

11.234.87.215 xx/16919 /dev/ocd_lp3 /etc/ddfa/pcf_lp3 # lp3 b2,p1

Create an entry for port ID via telnet. telnetd uses this entry to map the DTC ’s port and board numbers to the name being used for the connection on the HP-UX system:

11.234.87.215 02/01 terminal02

FILES

/etc/dpp
/etc/ocdbug
/etc/ocd
/etc/dpp_login.bin
/etc/utmp.dfa
/etc/newconfig/ddfa/pcf
/etc/newconfig/ddfa/dp

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