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Printer's IP address

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Alex Trishan

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Nov 5, 2020, 2:30:52 PM11/5/20
to
How do I find the IP address of a printer on my network? Thanks.

Eli the Bearded

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Nov 5, 2020, 3:14:44 PM11/5/20
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In comp.periphs.printers, Alex Trishan <alek.t...@gmail.com> wrote:
> How do I find the IP address of a printer on my network? Thanks.

I don't know. How do _you_?

I use nmap sometimes. I walk up to the printer and select the print
system information option sometimes. I walk up to the printer and find
it on the on-screen config menu sometimes.

With DNS service discovery, I can sometimes find the printer by name,
and not need the IP address:

$ lpinfo --include-schemes dnssd -v
network dnssd://Brother%20HL-L6200DW%20series._ipp._tcp.local/?uuid=e3212300-80ce-11db-8000-3c2af4123123
$

That is on Linux, YMMV with other operating systems. Your lack of detail
about the printer, the network, and the OS(s) involved doesn't help.

Elijah
------
Windows should have an nmap equivalent, maybe even called nmap

Stuart

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Nov 5, 2020, 6:34:07 PM11/5/20
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In article <ro1jt9$frn$1...@dont-email.me>,
Alex Trishan <alek.t...@gmail.com> wrote:
> How do I find the IP address of a printer on my network? Thanks.

If you log on to your router, there will be a page with a list of devices
and the I.P. addresses asigned to them. There will be something that
identifies your printer, perhaps something like Epson... and beside it you
should find your printer's MAC address and I.P. address.

--
Stuart Winsor

Tools With A Mission
sending tools across the world
http://www.twam.co.uk/

AnthonyL

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Nov 6, 2020, 7:15:41 AM11/6/20
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On Thu, 5 Nov 2020 14:30:51 -0500, Alex Trishan
<alek.t...@gmail.com> wrote:

>How do I find the IP address of a printer on my network? Thanks.

I'm a long time user of

https://angryip.org/

especially when it comes to sorting out my network but finds all
devices that have an IP on the same network.


--
AnthonyL

Why ever wait to finish a job before starting the next?

Chris Green

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Nov 6, 2020, 8:48:05 AM11/6/20
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Alex Trishan <alek.t...@gmail.com> wrote:
> How do I find the IP address of a printer on my network? Thanks.

Run a decent DHCP/DNS server on your LAN and the printer will have a
name. I use dnsmasq running on a Raspberry Pi and so all the systems
and devices on my LAN have names. No need to know IPs.

--
Chris Green
·

Arlen Holder

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Nov 24, 2020, 2:04:14 PM11/24/20
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On Fri, 06 Nov 2020 12:15:39 GMT, AnthonyL wrote:

> I'm a long time user of
> https://angryip.org/

I have a similar question, of greater detail, in that I know what my
printer IP address is, but I don't know how to find the _port_.

The reason the port matters is simply that some Android programs ask:
o How do you print from Android to your home networked printer on your LAN?
<https://groups.google.com/g/comp.mobile.android/c/nTAYljkvVl4>

Hence, I'll try this "angry IP" app to see what it tells me about my
o HP LaserJet 2100tn (connected on the same LAN subnet via Ethernet)

... My ad hoc sysinstall log follows...
mkdir x:\installers\network\scanner\angryip
<https://angryip.org/>
<https://angryip.org/download/#windows>
<https://github-production-release-asset-2e65be.s3.amazonaws.com...stuff>
Name: ipscan-3.7.3-setup.exe
Size: 3019446 bytes (2948 KiB)
CRC32: 8416A268
CRC64: 2646920C3D6D1BD8
SHA256: DF2BCA8190A27477227F92A6825DCE00FDA7E2F5C2A2A3DA67638B016FF62502
SHA1: 89177351A23D4EC1E2337273A9EE8271B077C1C7
BLAKE2sp: 7D7570FF0FF539488AA7ED3FF925A54596AD5375A934DD40F32C637D9C4DFB45
Run this IP Scanner 3.73 installer executable
It wants to go in C:\Program Files\Angry IP Scanner
I put it where it belongs C:\app\network\scanner\angryip
Note: You decide that; not a thousand different companies.
It installs quickly, with no obvious shenanigans (good).
Create a shortcut C:\menu\network\scanner\ipscan.lnk
Target C:\app\network\scanner\angryip\ipscan.exe
Start it: Taskbar > menu > network > scanner > ipscan
Uncheck [x]Send anonymous error reports
Hit [Next] quite a few times, and then [Close]

I'm not sure what to do next but I hit the big green "Start" button.
Aha! Up pops a Windows Defender Firewall blockage report:
Java(TM) Platform SE binary
C:\program files (x86)\common files\oracle\java\javapath_target_18549781\javaw.exe

Scanning completed (it took about 20 seconds).
o IP Range 192.168.0.1 - 192.168.0.255
o Hosts alive: 9
o With open ports: 6

OK. I scroll down to find the printer, which doesn't show up "as" a
printer, but I happen to already know its IP address, where it says:
o IP = 192.168.0.20
o Ping = 2ms
o Hostname = [n/a]
o Ports[3+] = 80

I'm not sure what the "3+" means, but the rest seems pretty clear.
o Thanks for this advice to use this freeware Windows network scanner.

AnthonyL

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Nov 25, 2020, 8:36:09 AM11/25/20
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I think at various times I've had AngryIP blocked by various av
software etc despite it having been around a while

Others may have guidance on port scanning but there is another thread
on printing to windows 10 and it notes that AngryIP can scan for open
ports (Options-Select Ports ie range).

Arlen Holder

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Nov 25, 2020, 3:21:04 PM11/25/20
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On Wed, 25 Nov 2020 13:36:06 GMT, AnthonyL wrote:

> I think at various times I've had AngryIP blocked by various av
> software etc despite it having been around a while

Thank you very much for your purposefully helpful advice on ipscan.

I don't use AV programs so I'm fine with AngryIP ipscan, which I like.
o AngryIP ipscan is simple - it just scans for devices & open ports

What it found for my printer turned out to be correct
o I hadn't realized my printer had port 80 open, but it did!
<http://192.168.0.20:80> brought up an HP JetScan help document

> Others may have guidance on port scanning but there is another thread
> on printing to windows 10 and it notes that AngryIP can scan for open
> ports (Options-Select Ports ie range).

In another thread, I'm trying to get printing to work from Android
directly from my Android phone (on my LAN via Wi-Fi) to the Ethernet'd
printer (on my LAN on the same subnet).
o Do you use Windows to print from your Android to your printer?
<https://groups.google.com/g/alt.comp.microsoft.windows/c/6ScU1H5Q43U>

One thing that comes up is "CUPS", which seems to use port 631 by default.
o <https://i.postimg.cc/6qRSK6WY/printing11.jpg> Turn CUPS print server on
o <https://i.postimg.cc/9fMnMYX4/printing12.jpg> CUPS wants to use port 631

That begs the question of "what port" do printers normally use anyway?

AnthonyL

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Nov 27, 2020, 7:34:12 AM11/27/20
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I've never printed from my Android but I've just switched my Epson
X)-6005 on which is connected to my WiFi (and a direct USB to my
notebook).

I then followed the Android's Help which says to go Connected Devices,
clicked on Connections preferences and then Printing which after a few
seconds found my Epson via Default Print services.

I don't know if there is a normal and I don't know which my setup
would use. I thought 80 was an output port only.

Another app I find useful is Port Authority which is available from
Fdroid. Quick scan of all your network and a port check too. If
you're not using the Fdroid repositiory you should have a look. I go
there nearly always in preference to Play Store and have a number of
useful apps, some of them the same as Play Store but without ads!!

hth

AnthonyL

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Nov 27, 2020, 11:43:15 AM11/27/20
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On Fri, 27 Nov 2020 12:34:10 GMT, nos...@please.invalid (AnthonyL)
I've just printed something out, quite easily once I selected
colour/mono as an option. I wonder if Port 80 is to deliver printer
information and one of the other Ports to send the printing to?

Arlen Holder

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Nov 27, 2020, 1:08:56 PM11/27/20
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On Fri, 27 Nov 2020 12:34:10 GMT, AnthonyL wrote:

> I've never printed from my Android but I've just switched my Epson
> X)-6005 on which is connected to my WiFi (and a direct USB to my
> notebook).

Hi AnthonyL,

Thanks for that purposefully helpful advice, where you'll find a lot more
information about this problem set over here, in comp.mobile.android:
o How do you print from Android to your home networked printer on your LAN?
<https://groups.google.com/g/comp.mobile.android/c/nTAYljkvVl4>

While I am ecstatic that printing works so easily for you with your Epson
XP-6005 printer, you have a completely different setup, I think, and that
matters a lot (unfortunately for me).
o EXPRESSION PREMIUM XP-6005 Wi-Fi all-in-one
<https://www.epson.de/en/products/printers/inkjet-printers/for-home/expression-premium-xp-6005>

My printer is an HP LaserJet 2100tn (which has an Ethernet card):
a. Mine is not wi-fi enabled
b. Mine is not hooked up to a PC via USB (or anything other than a router)
c. Mine is hooked directly to the router via Ethernet

While even with my setup it's easy to print if I use the "cloud" as the
printer driver, the goal is to print using our own LAN.

I am exploring _some_ solutions (many of which are from F-Droid), as the
whole goal is to come up with a solution that not only benefits me, but,
that benefits everyone else at the same time (who has the same problem).

One issue I have in debugging is understanding the role of:
a. Where is the "printer driver" when printing from Android?
b. Who is the "printer server" when printing from Android?

Those two questions are ones I never thought about until I needed to debug
why it's so simple to print from Windows over the LAN, but not Android.

AnthonyL

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Nov 28, 2020, 4:15:45 AM11/28/20
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On Fri, 27 Nov 2020 18:08:54 -0000 (UTC), Arlen Holder
<arlen_...@newmachines.com> wrote:

>On Fri, 27 Nov 2020 12:34:10 GMT, AnthonyL wrote:
>
>> I've never printed from my Android but I've just switched my Epson
>> X)-6005 on which is connected to my WiFi (and a direct USB to my
>> notebook).
>
>Hi AnthonyL,
>
>Thanks for that purposefully helpful advice, where you'll find a lot more
>information about this problem set over here, in comp.mobile.android:
>o How do you print from Android to your home networked printer on your LAN?
><https://groups.google.com/g/comp.mobile.android/c/nTAYljkvVl4>
>
>While I am ecstatic that printing works so easily for you with your Epson
>XP-6005 printer, you have a completely different setup, I think, and that
>matters a lot (unfortunately for me).
>o EXPRESSION PREMIUM XP-6005 Wi-Fi all-in-one
><https://www.epson.de/en/products/printers/inkjet-printers/for-home/expression-premium-xp-6005>
>
>My printer is an HP LaserJet 2100tn (which has an Ethernet card):
>a. Mine is not wi-fi enabled

Shouldn't matter - see c.

>b. Mine is not hooked up to a PC via USB (or anything other than a router)

That was just a comment. On the PC I can print wirelessly or direct.
Direct (USB) is quicker. The PC is not used as a shared printer so
anything else prints over the LAN

>c. Mine is hooked directly to the router via Ethernet

Shouldn't matter whether it is Ethernet (not tried) or WiFi providing
you are on the same LAN.

>

>While even with my setup it's easy to print if I use the "cloud" as the
>printer driver, the goal is to print using our own LAN.
>

Ah! HP. Good fun. Took ages for me to get my neighbours printing from
her iPad to her HP wirelessly. HP wanted to go through the cloud and
back via an email. The instructions appeared to me to be as clear as
mud.

In the end it required the installation of the HP app onto the iPad
then it worked providing it was initiated by the iPad. (The Mac
allows scanning to be initiated by the printer).

>I am exploring _some_ solutions (many of which are from F-Droid), as the
>whole goal is to come up with a solution that not only benefits me, but,
>that benefits everyone else at the same time (who has the same problem).
>
>One issue I have in debugging is understanding the role of:
>a. Where is the "printer driver" when printing from Android?
>b. Who is the "printer server" when printing from Android?
>

I don't know, and thus far for me it doesn't seem to matter.

>Those two questions are ones I never thought about until I needed to debug
>why it's so simple to print from Windows over the LAN, but not Android.

When I run a Port scanner on my Epson IP I get quite a list of Open
Ports, more than I expected. Epson have a page showing the Open Ports
and what each does (well all except 139 which of course is necessary
for SMB/Netbios and I don't know why they didn't show that in the
chart). Anyway all the Open Ports correlate to and an item on that
page.

If Port Scanner can see your printer and Open Ports then there must be
some other issue. If it can't then there you have to diagnose whether
it can't see the IP, can't see the Ports etc. That may be down to a
router/firewall setting perhaps?

Sorry I've not looked at the other threads - too much going on for me
to sift through. And I'm not an expert though I generally manage to
get things working for friends and family.

Just an addition, I have no problem printing over the LAN from my
Linux install either. so Windows, Android and Linux all ok.

AnthonyL

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Nov 28, 2020, 4:22:19 AM11/28/20
to
On Sat, 28 Nov 2020 09:15:43 GMT, nos...@please.invalid (AnthonyL)
wrote:

>On Fri, 27 Nov 2020 18:08:54 -0000 (UTC), Arlen Holder
><arlen_...@newmachines.com> wrote:
>
>>On Fri, 27 Nov 2020 12:34:10 GMT, AnthonyL wrote:
>>
>>> I've never printed from my Android but I've just switched my Epson
>>> X)-6005 on which is connected to my WiFi (and a direct USB to my
>>> notebook).
>>
>>Hi AnthonyL,
>>

<snip>

Just did a nice helpful reply - actually I think there are one or two
clues that may have helped - then saw the other thread in which you've
solved it.

Sort of mirrored my HP exeperience cited in the previous post.

Anyway well done. Just love the way IT gets easier as systems mature.
What do they* do, put script-kiddies on new projects?

*Not restricted to HP.

Arlen Holder

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Nov 28, 2020, 9:13:30 PM11/28/20
to
On Sat, 28 Nov 2020 09:22:17 GMT, AnthonyL wrote:

> Just did a nice helpful reply - actually I think there are one or two
> clues that may have helped - then saw the other thread in which you've
> solved it.

Hi AnthonyL,

I thank you and appreciate your purposefully helpful advice.
o All of us are volunteers - we pitch in together to help each other

As you noted, printing has gotten easier over time, at least from Windows &
Linux it has, where Linux (with CUPS) was even easier than Windows years
ago; but both are seamless nowadays (although Windows drivers are a PITA
when HP no longer supplies them on their web site, & neither does Win10):
o Tutorial for the EASIEST (maybe only?) way to install a problematic legacy printer such as the HP LaserJet 2100 on Windows 10 current versions
<https://groups.google.com/forum/#!topic/alt.comp.freeware/Qb-fXNOH_8g>

Also as you noted, the only requirement for the printer "should" be that
it's on the LAN (no matter _how_ it's hooked up to that LAN subnet).

(1) Cloud solutions
Like you, I found out a lot of the highly marketed solutions require the
cloud, which is, I think, this data flow (I'm not fully sure though)
a. You press a print button which sends your document to a server
b. That server renders that document in the proper format (e.g., PCL-5)
c. That server sends the rendered results (e.g., PCL-5) back to you
d. And then your app sends that PCL-5 to the printer over your LAN

(2) Local PDF solutions
I also found a bunch of so-called "local" solutions, which didn't render
all that much it seems; they just send the PDF directly to the printer,
which would work fine (I guess) for a printer that directly accepts PDF.

(3) OEM Brand-name solutions (e.g., HP, Epsom, Brother, etc.)
I tried the OEM HP-branded solution, but it simply failed for whatever
reason. It only had the choice of Wi-Fi or Wi-Fi direct, so I suspect that
it failed simply because it was designed for a Wi-Fi enabled printer only.

(4) Mopria solutions
I tried a bunch of these until I realized that they're _all_ scams
(AFAICT), since Android _already_ comes, native, with a "Mopria" print
server (as its default print server). Even so, they can't work, I think,
simply because my printer, built in 1999, isn't Mopria compliant.

(5) CUPS Server solutions
I only halfheartedly tried the "CUPS Server" solutions, in that I installed
them on my phone; but they seem to require a cups server somewhere, where I
couldn't find CUPS software for Windows (I found it for Linux). While I
dual boot, it's more often in Windows than it's in Linux, so that's not a
good solution for me unless it was the only way to do it (and it wasn't).

(6) Windows SMB shares solutions
I contacted the Windows newsgroup asking for sharing solutions, but none
were forthcoming, and, besides, it turns out I didn't need to go this far
(although I would have had I not found another solution). It's strange
though, that Windows 10 prints just fine, and Android is so difficult, but,
if you were to ask me today, I could get you up and running in minutes just
because I now know how to do it and I didn't know then.

(7) Windows USB shares solutions
As with the SMB shares, I didn't explore directly connected computers,
although others who posted to the thread claimed they work just fine.

(8) There was only one solution (so far) that actually worked!
This solution turned out to be, as many tend to be, devilishly simple!
o Note: I almost never fail, if ever, in solving technical problems.

*How to print from Android to an Ethernet-only HP PCL-5 printer on your LAN*
a. On Android, I installed a "print server" which outputs PDF level 1.3
<https://play.google.com/store/apps/details?id=com.blackspruce.lpd>
b. But my printer doesn't accept PDF - my printer wants PCL-5 instead
<https://support.hp.com/us-en/product/hp-laserjet-2100-printer-series/25469/model/14918>
c. So I added a muPDF "faux printer driver" to "render" the PDF to a bitmap
<https://play.google.com/store/apps/details?id=com.blackspruce.mupdf>

Somehow, the _combination_ (with judicious settings applied) converts the
PDF to a bitmap and by some magic, then to PCL-5, which is then sent to the
printer via the Android "print server".
o <https://groups.google.com/g/comp.mobile.android/c/nTAYljkvVl4/m/qnuazdahCAAJ>

I do not profess nor pretend to know _how_ it works; but it works.
o I must say this is documented NOWHERE on the entire Internet (AFAICT).

Since the main purpose of my posts once a problem is resolved is to
leverage that solution to others so that they don't have to go through the
hell I did, here are, physically, the steps that will solve this problem.

A. If necessary, figure out your printer's IP address on your LAN:
o Printer's IP address, by Alex Trishan
<https://groups.google.com/g/comp.periphs.printers/c/Y-b186tFKTs>

B. Test that the Android device can connect to the printer's IP address:
AndroidTermux: ping 192.168.1.20

C. Determine if your printer can support PDF level 1.3
Note: I don't know programmatically how to determine this information,
but if you try to print from Let's Print Droid, it will pretty much
tell you that it needs Let's Print PDF in order to print PCL-5.

D. If your printer can't support PDF level 1.3 directly, then install
this "faux printer driver" which renders PDFs into bitmaps (I think):
o Let's Print PDF, by BlackSpruce (note it uses muPDF code)
<https://play.google.com/store/apps/details?id=com.blackspruce.mupdf>
Note: As always, this APK is free, ad free, cloud free, & google free.

E. Then install the companion "Let's Print Droid" print server APK
o Let's Print Droid, by BlackSpruce
<https://play.google.com/store/apps/details?id=com.blackspruce.lpd>
Note: As always, this APK is free, ad free, cloud free, & google free.

As a side note, I don't use Google Play as I don't ever use Google
products if I don't have to; so I use the Aurora Store, which is better.

F. After installing both programs, you have to also know a few more tricks
in terms of setting up the Let's Print Droid "print service".

I only found out these tricks by pure trial and error; so not only
is there likely a better way, but some of the tricks may be wrong.

a. The first is to disable Apple Bonjour mDNS scanning
(it simply doesn't work and just wastes your time overall)
b. Another is you need to "manually configure" the printer in LPD
(where I hit upon the settings below by almost sheer trial & error)
Printer Name: HP LJ 2100 tn <== this isn't critical
Protocol: RAW - Jet Direct <== there are 13 protocols to choose from
IP Address/Computer Name: 192.168.0.20 <== it's a static IP address
Port Number: 9100 <== this was the default, so I kept it that way
Queue/Share/Dir Name: DROID <== this was the default, which I kept
Page Description Language: PCL - HP-PCL5 Black/White <== 8 choices
c. You need to make sure Let's Print Droid is the _only_ print server
turned on in the Android Settings "Print Service" menu
(which you can easily make a shortcut to if you follow this thread)
o Creating quick-access shortcuts to any Android or App setting page
<https://groups.google.com/g/comp.mobile.android/c/_1oTdgCIpkc>

Note: The "trial and error" choices for the "protocol" setting above are:
o LPR - Line Printer Remote
o RAW - Jet Direct
o SMB - Windows Shared Printer
o GCP - Google Cloud Print
o IPP - IPP/CUPS print server
o IPPS - IPP/CUPS SSL server
o HTTP - Web Server POST
o HTTPS - encrypted POST
o FILE - CIFS/SMB File drop
o FTP - File Transfer
o FTPS - File Transfer SSL
o SHARE - Share PDF with another app
o VIEW - View PDL with another app

Note: These are the trial & error Page Description Language (PDL) choices:
o RAW - image files not rendered to PDL
o Jpeg Image
o PCL - HP-PCL5 Black/White
o PCL-C - HP-PCL5-C Colour PCL
o PS - Postscript
o PDF - Portable Document Format
o PCL-XL - HP PCL 6 colour,b/w
o URF - Apple AirPrint Universal Raster

While there may be other settings that will likewise work, those are what
worked first for me given my Ethernet'd HP LaserJet 2100tn printer which is
connected by CAT5 cable directly to the SOHO router.

Note: I haven't yet tested anything but PDF files as I wanted to keep the
problem set as simple as possible while I'm setting it up & testing.

The printing process that worked first after the setup above was:
1. Tap the homescreen "Let's Print Droid" icon (which I renamed LPD)
2. Inside the "Let's Print Droid" app, tap the "Print A File" icon
3. In the resulting file browser navigate to your PDF file
4. That brings up not the PDF file, but the default print settings
5. Keep or change the print settings as desired, & press [Continue]

That's it.
o Every page of your PDF file to be printed will be rendered on your phone.
o Once all pages are rendered, they will then be sent to the printer
o Note that a huge PDF will consume a lot of your phone's memory
(My 64GB $100 Moto G7 has 4GB of memory so it didn't flinch yet.)

Key technical issues which remain to be resolved:
a. It would be nice to eliminate the Let's Print PDF renderer if possible
(This will likely take trial & error on the protocol settings.)
b. But mainly I need help from experts in figuring out what's going on!
(I need to better understand what's actually happening when I print.)
c. Is either of these two flows what is actually happening to the data?
PDF -> LetsPrintPDF -> bitmap -> LetsPrintDroid -> PCL5 -> printer
PDF -> LetsPrintPDF -> bitmap -> PCL5 -> LetsPrintDroid -> printer

See also this Google Group, apparently, for the Let's Print Droid app:
o <https://groups.google.com/g/lets-print-droid>
--
As always, please improve so all benefit from every action we take.

Arlen Holder

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Nov 29, 2020, 11:07:04 PM11/29/20
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On Tue, 24 Nov 2020 19:04:08 +0000 (UTC), Arlen Holder wrote:

> OK. I scroll down to find the printer, which doesn't show up "as" a
> printer, but I happen to already know its IP address, where it says:
> o IP = 192.168.0.20
> o Ping = 2ms
> o Hostname = [n/a]
> o Ports[3+] = 80

I think, perchance, the ipscan lied to me.
o Or maybe it's just the wrong tool to find the printer's ports

Note that it turns out HP printers use, by default, port 9100.
o So the question is why didn't port 9100 show up in the scan?

This is a quick test of port 9100 on my printer over the LAN:
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)

So my HP LJ 2100tn is listening on port 9100.
o But then, why didn't the ipscan show that to be the fact?

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

Notice they _also_ confirm LPD automatically chose port 9100.
o <https://i.postimg.cc/bYS12Dqm/printing15.jpg>

Does anyone know why the ipscan didn't catch that HP's use port 9100?
--
Usenet pools our collective experience with people around the world.

AnthonyL

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Nov 30, 2020, 8:02:52 AM11/30/20
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As mentioned previously try the Android app Port Scan from the Fdroid
repositiory.

Arlen Holder

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Dec 1, 2020, 5:17:10 AM12/1/20
to
On Mon, 30 Nov 2020 13:02:50 GMT, AnthonyL wrote:

> As mentioned previously try the Android app Port Scan from the Fdroid
> repositiory.

Hi AnthonyL,
Thank you for reminding me of that, which, I openly admit, I had forgotten.
o You'd think a Windows port scan would find open ports on a printer

I use AuroraDroid instead of F-Droid (same thing, only with a better GUI,
e.g., it autosaves APKs, just as I use Aurora Store instead of Google Play)
o Port Authority, Port scanner
<https://f-droid.org/en/packages/com.aaronjwood.portauthority/>

It turns out I already had that F-Droid app in my "Network" folder:
o <https://i.postimg.cc/L4YqhR1P/printing16.jpg>

Pressing "Discover Hosts", it found the printer easily at:192.168.1.1
o 192.168.0.20 HP-UX E 9000/889

Then I tapped that particular entry & hit "Scan Well-Known Ports"
o Which scanned the first 1024 ports, finding these "Open Ports"
23 - Telnet
80 - World Wide Web HTTP
280 - http-mgmt
515 - spooler
631 - IPP (Internal Printing Protocol)

That was interesting. For example, noting that CUPS is often using port
631, does that mean my printer is already cups server of its own right?

Curious, I hit the button to scan the entire 65K port range, which found:
23 - Telnet
80 - World Wide Web HTTP
280 - http-mgmt
515 - spooler
631 - IPP (Internal Printing Protocol)
9100 - PDL Data Streaming Port

So there it is, in stark black & white.

Not only is the default PCL-5 printer port clearly 9100
o But, apparently, I have "IPP" (is this the same as CUPS?)

Looking it up, it seems IPP is the _only_ protocol CUPS supports natively:
o Cups protocol: What's the difference between RAW/JetDirect, IPP, IPP14, LPD?
https://unix.stackexchange.com/questions/333296/cups-printing-protocols-whats-the-difference-between-raw-jetdirect-ipp-ipp>
--
Together we know more than any one of us can possibly know being all alone.

Andreas Kohlbach

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Dec 15, 2020, 5:47:09 PM12/15/20
to
On Tue, 24 Nov 2020 19:04:08 +0000 (UTC), Arlen Holder wrote:
>
> On Fri, 06 Nov 2020 12:15:39 GMT, AnthonyL wrote:
>
>> I'm a long time user of
>> https://angryip.org/
>
> I have a similar question, of greater detail, in that I know what my
> printer IP address is, but I don't know how to find the _port_.

Tried nmap on Linux?

I found an Officejet 6600 on the sidewalk and after it was still there
after hours I took it home. Print head was jammed so it did strange
grinding noises. After freeing it the printer did some maintenance and
worked. To my amazement the cartridges were 75 to 80% full.

Anyway I was able to get it running using CUPS when I used the PC as WIFI
hotspot (although I have to use a black ad white driver as the driver
found automatically refused.

It also works when I start the printer with its own WIFI. But if I put it
into the home WIFI it can't be found by hp-setup or the CUPS web
interface. A port scan says:

Not shown: 997 closed ports
PORT STATE SERVICE
111/tcp open rpcbind
139/tcp open netbios-ssn
445/tcp open microsoft-ds

No printer ports, like 631, 515 or web interface (80). They show only
when the printer creates its own WIFI hotspot. I don't know why.
--
Andreas

PGP fingerprint 952B0A9F12C2FD6C9F7E68DAA9C2EA89D1A370E0

Andreas Kohlbach

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Dec 15, 2020, 5:49:56 PM12/15/20
to
On Thu, 5 Nov 2020 14:30:51 -0500, Alex Trishan wrote:
>
> How do I find the IP address of a printer on my network? Thanks.

If Linux, fping comes handy. Assuming your WIFI network is 192.168.0.0/24
then

fping -g -a -q 192.168.7.0/24

finds IP of connected devices. 1 (last octet) is usually your WIFI
router. My printer got 254 assigned.
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