Arlen Holder wrote:

On Mon, 30 Nov 2020 03:14:09 +0000 (UTC), JT wrote:

HP printers use TCP port 9100 by default

Hi JT,

Thank you for your purposefully helpful information about the port that the
HP printers use by default being port 9100. Much appreciated.

I instantly ran this quick test the moment I saw your post:
o telnet 192.168.0.20 9100 (connects, but I can't talk printer protocol)
o telnet 192.168.0.20 9200 (fails, I chose that port arbitrarily to test)

Indeed, you are correct that the HP LJ 2100tn is listening on port 9100.
o Thank you for being a good netizen by helping others out.

I wonder why port 9100 didn't show up in the ipscan for that printer?
o Printer's IP address, by Alex Trishan
https://groups.google.com/g/comp.perips.printers/c/Y-b186tFKTs
o IP = 192.168.0.20
o Ping = 2ms
o Hostname = [n/a]
o Ports[3+] = 80

I checked the automatically set settings in Android LetsPrintDroid:
o https://i.postimg.cc/L5Pfd7xc/printing14.jpg

Notice they also confirm they automatically chose port 9100.
o https://i.postimg.cc/bYS12Dqm/printing15.jpg

Do you perchance know what the "RAW" means in the "RAW - Jet Direct"
o Is that "RAW" format the same thing as "PCL-5" format?

Arlen,

RAW is the default protocol on HP printers.

The other option is LPR/LPD.

I would highly recommend using RAW.

LPR/LPD gives you options for creating a print queue and send info about the job.

Not really needed in a home environment.

More info about LPR/LPD: https://www.brooksnet.com/content/faq-what-is-lpr-lpd


This entirely different from printer language.

Most HP printers support PCL5, PCL6 and Postscript printer languages.

PCL6 would be my choice if you don't need Postscript or your printer doesn't support it.


In addition, some HP printers do NOT allow Telnet access.



JT

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