PRN: LPD / LPR Printing


LPD / LPR PRINTING



Description:  An LPR utility lets an application on one computer print to a spooler on a remote computer. The receiving component is called a line printer daemon (LPD).  Both utilities are included in Print Services for UNIX.  For the vast majority of network-connected print devices, the standard TCP/IP port is the best choice and should be used if possible.  Standard TCP/IP ports are faster, more scalable, and bidirectional.






















LPR (RFC 1179 Compliant) Standard TCP/IP Port Monitor
Limited to source ports 721-731 Source ports from ephemeral ports (9100 default)
Four-minute timeout per port No source port timeout
Unidirectional – single error status reporting Uses SNMP for rich status and error reporting
Control file requires double spooling for accurate byte count Single-file spooling enabled by default.  Configurable through port properties
Prints to destination port 515 Prints to destination port 515 in LPR mode


 


Scoping the Issue:  We need to know what versions of the operating system(s) are involved from both the Unix and Windows side.  Depending on the issue in question, the data required may vary.


 


Data Gathering:  In all instances, collecting either MPS Reports with the General, Internet and Networking, Business Networks and Server Components diagnostics, or a Performance-oriented MSDT manifest must be done.  Additional required data may include:



  • A Network trace captured during print issues (from both the source and destination systems)

  • Export the HKLM\SYSTEM\CurrentControlSet\Services\LPDSVC key

 


Troubleshooting / Resolution:  After you have gathered the data, there are some things to check:



  • MPS Reports:

    • Review the Event Logs for relevant events – specifically look for Event ID 26 (Application Popup), Event ID 1000 (Application Error) and Event ID 7034 (Service Control Manager) messages that correspond to the times that you are seeing issues

    • You should also check the Event Logs and Windows Update logs to see if there were any application updates or patches that preceded the unexpected behavior – there may be a correlation

  • Verify that the TCIP/IP Print Server Service is running

  • Verify that the target printer works as expected with a Standard TCP/IP port

  • Enable the UseNonRFCSourcePorts configuration option – see Microsoft KB Article 179156 for more information

  • If you are using a Standard TCP/IP port in LPR mode, toggle the “LPR Byte Counting Enabled” option in the port settings

 


Additional Resources: