tcp checksum error from JetDirect printer

[Mark Landin]

I'm trying to get my Colorpro CAD working with my HP-UX 11.11 systems. Using tcpdump to watch the packets, and using the JetAdmin stuff in 11i to send test files to the printer, I am seeing tcp cksum errors in packets sent from the printer back to the HP-UX system. This occurs as I try to send the color HP-GL/2 file to the printer. The printer never prints anything and doesn't even act like it's receiving anything. After the checksum error, I don't see much in the way of traffic between the system and the printer except for periodic handshaking stuff.

Does this indicate my Jetdirect card (j4110A) is likely bad?

[Jeff Schussele]

Hi Mark,

It's a big clue.
It's probably either JetDirect, cable or hub/switch port.

How does a dumb old ascii text print job do?
Do you get any output from it?

Rgds,
Jeff

[Michael Steele_2]

Sounds like the printer buffer is over flowing from the tests with color HP-GL/2 files.

Does the same happen with ascii text?

[Patrick Wallek]

Are you ABSOLUTELY SURE that this particular printer support HP-GL/2?

[Mark Landin]

It does pass the ascii test file, and the color PCL test. It won't do the color PS test or the color HP-GL/2 test.

The Colorpro CAD, HP model C7777A, does support HP-GL/2 ... in fact it says "HP-GL/2" right on the front of it! We also added the Postscript upgrade so it will do Postscript Level 3 also. It has 52MB of memory (a wierd number, I know).

Since the JetAdmin diagnostics don't use the spooler, I can't see the file sizes being sent to the printer to know if the HP-GL/2 or PS files are huge files or not.

[Mark Landin]

OK update:

- I tried another JetDirect card. I also saw the tcp checksum error using that card, so I'm going to assume it's a "feature", not that I have two buggy cards.

- I found the testfiles and they are not large .... all under 1K, in fact, except for the color PS.

- Anyway, during all of this dinking around with the printer, it's working now! Go figure. It passes all the tests and prints from my applications as it should.

Case closed! Thanks to all who played along...