This document explains the differences between the LPD (Line Printer Daemon) and Stream printer protocols and what it means to your network and your connection to a remote host.
LPD protocol is the standard printing protocol on UNIX systems. There are two parts to the protocol: a client and a server.
There are two parts involved in the transfer of a print file itself: the data file and the control file. The data file (DF) contains the data to be printed. The control file (CF) is the file that tells the remote host or remote printer how to print the file. The data file is sent to the printer first, followed by the control file.
Note: These are not recommendations, but the way the LPD protocol functions.
To confirm these settings, follow these steps:
$ multinet configure/server server-config> sh /full LPD Service "LPD": TCP socket (AF_INET,SOCK_STREAM), Port 515 Socket Options = SO_KEEPALIVE INIT() = TCP_Init LISTEN() = TCP_Listen CONNECTED() = TCP_Connected SERVICE() = Run_Program Program = "MULTINET:SERVER_LPD.EXE" Accept Hosts = IP-127.0.0.1 Accept Nets = IP-22.214.171.124 , IP-126.96.36.199 Reject by default all other hosts and nets Reject Message = "Your host does not have line printer access"
In this example, this LPD server will accept requests from itself, and any host that is on the 188.8.131.52 and the 184.108.40.206 subnets.
If a host is on a different subnet, 220.127.116.11 for instance, the reject message text will be returned.
$ show log *lpd* (LNM$SYSTEM_TABLE) "MULTINET_LPD_DEFAULT_USERNAME" = "DEFAULT"where "DEFAULT" is a UAF entry on the server system.
Define this logical to allow a user who does not have a VMS account on this system to print as the default user.
Note: The username "DEFAULT" must exist on the server system. It does not need to have any privileges and it can be disabled, but it must exist.
$ show queue 'queue name'
If the queue is not there, even a user who has an account cannot print.
When setting up an LPD print queue that points directly to a printer, then you must supply a remote-queue-name that the remote printer's Ethernet card knows about. You may actually have to configure a print queue on the card. The HP JetDirect cards that come with most HP printers have three predefined queues for the LPD protocol:
Sample LPD Client Config
$ mu config/print MultiNet Remote Printer Configuration Utility V3.5(23) [Reading in configuration from MULTINET:REMOTE-PRINTER-QUEUES.COM] PRINTER-CONFIG> PRINTER-CONFIG>add HOBBES_LPD_HP5_PS Destination IP Address: [18.104.22.168] Protocol Type: [LPD] Remote Queue Name: [post] [HOBBES_LPD_HP5_PS =3D> 22.214.171.124, post] PRINTER-CONFIG>exit $
With Stream printing, there are no network overhead issues and no control files or Protocol-layer communications. Stream simply opens a socket to the remote IP address and sends data to it. The printer receives the data and starts printing. There is no buffering.
Before you begin, you need to know the following:
If you need to confirm this information is correct, do the following:
Usually if you cannot do either step 1 or 2, your print queue will stall.
Sample Stream Protocol Config
$ mu config/print MultiNet Remote Printer Configuration Utility V3.5(23) [Reading in configuration from MULTINET:REMOTE-PRINTER-QUEUES.COM] PRINTER-CONFIG>add HOBB_TK_TEST Destination IP Address: [126.96.36.199] Protocol Type: [STREAM] TCP Port Number:  [HOBB_TK_TEST =3D> 188.8.131.52, TCP port 9100] PRINTER-CONFIG>exit $
Use the LPD protocol if one of the following applies:
Note: People often use LPD to print to HP printers, but we recommend using Stream.
Use Stream protocol when you are printing to printers directly or to terminal servers.