HPUX/LP automatically disabling printers

[Brad_Edwards]

I support an HPUX 11.11 print server that delivers print to several business parter printers. These business partner printers have special network configurations as they only seem to have port 9100 open to them, and I don't know how to determine if the open 9100 port is bi-directional or not. I cannot use WJA or hpnpadmin to collect information about them.

I have always known that HPUX/LP will occasionally have problems recovering if one of those printers goes off-line, runs out of paper, is power-cycled, etc, and I had a script that was running every 15 minutes or so to disable/enable those devices to make sure no print was backing up. Lately, the customer is reporting a much greater frequency of this problem, and they are reporting problems nearly every morning. I've had to modify my script to be faster when disabling/enabling these queues and now it runs every 3 minutes in cron!

I'm looking for any documentation or explanation for this kind of behavior, since the customer would like a root cause for the problem to see if the disable/enable script is the best solution. Any assistance anyone can provide would be greatly appreciated. Thank you!

[TTr]

You need to check if anything changed in the way the printer users use the printer. I had cases where the people on the printer site were hitting the online/offline button to stop the printing so that they could retrieve the printed jobs and look through them. Also they were opening the printer trays to put in special paper or letterhead etc. Another area to look at is the network. Is the connection flaky or slow? Since they have port 9100 only open, obviously you can not do any network troubleshooting on your end. If your busines partner needs an RCA they need to pay you to go to their site to observe what happens or make their resources available to you for troubleshooting. Sorry but nothing much to go with here and I have no other documentation to offer you.

[Bill Hassell · Accepted solution]

This problem will require a lot of networking help. You indicate business partners so I assume that you are printing over a WAN or even the (100% unsecured) Internet. The lp spooler is quite simple -- it simply runs the printer script. For HP printers using port 9100, the JetDirect script hpnpf does all the work. You can see it in the /etc/lp/interface directory as part of the base script that drives JetDirect printing.

Now hpnpf has a lot of good debugging capability and can trace the activities performed during a print job. This will require a *lot* of log space but the end of the log (with a failed job) will be the most useful. You should also monitor the network with Wireshark. My guess is that you'll see a fairly sick network, especially using Wireshark. Until the network is fixed (firmware in routers, config settings for WAN interfaces, etc), the printers will continue to be disabled.

Also make sure that you have disabled True End Of Job and Job Recovery as these can be unreliable in a noisy network. Use modifyqueue to tunr these off:

modifyqueue -q some_prn -r off -t off

[Brad_Edwards]

A quick update on this problem. The customer's network team has confirmed some recent updates to the network configuration for the business partner which may explain the higher frequency of this issue, but now a new problem has developed.

Since I increased the frequency of our disable/enable script to re-initialize these printers, we have occasionally been seeing jobs get "stuck" in the queues and they start printing over and over until they are manually cancelled. Has anyone seen this behavior before? Is there any way to mitigate it?

[DeafFrog]

Hello Brad ,
Pls. check this for hints :

/var/spool/lp/log
/var/spool/lp/lpana.log
/var/spool/lp/lpd.log

check /var/spool/lp/request/

[TTr]

> they start printing over and over until they are manually cancelled

This is most likely caused by the true end-of-job setting in conjuction with very bad network. It looks like things have gotten so bad that not even a single job completes succesfully and it gets reprinted. Check out the man page for hppi.

[Bill Hassell]

TTr has the answer. Run through EVERY printer on your system with modifyqueue and turn off TEOJ as well as job recovery:

modifyqueue -q -t off -r off

There are other options you can disable (or enable) with this 1-liner.