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Not able to get data on tcp port==9100

asked 2022-03-12 08:43:50 +0000

pravinpednekar gravatar image


I am trying to capture the details of printer port 9100. But there is no details found in that. When we capture specific printer IP address. Problem is when we give the print command for Qty= 2000 labels for printing on printer .Its loss some labels to printing(Some time 800 or some times 500 labels was not able print).Printer is not hang when we check printer is stop for printing. Some times Its printed Qty=1200 .Some times printed 800 labels .So most of the time label is lost to print the labels. We are able to capture IP address but not able to capture the data on port 9100. we try to check which command is trigger on printer and why printer is not able to print all those labels. I am trying first time on Wireshark to capture the data s and may be i did mistake to config in Wireshark .

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As mentioned in the answer and comments, it would help if you described your network in terms of the printer, what it's connected to (switch etc.) the host machine that's running Wireshark and what it's connected to and any other items in the network that may be relevant.

grahamb gravatar imagegrahamb ( 2022-03-15 13:53:29 +0000 )edit

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answered 2022-03-13 17:56:00 +0000

André gravatar image

If you're sure that the printer communicates over port 9100 and you don't see it in the capture (using promiscuous mode) then it is most likely the traffic did not pass the point in the network were you did the capture.

Take a look at

Since nowadays networks uses switches you'll need a tap or a (managed) switch in monitor mode to capture the traffic to/from this device.

And when the printer is using WIFI then take a look at this: , or use the monitor mode of the Access Point.

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Is the printer wireless or wired? You can sniff the wired side if you have a TAP or switch that supports mirror ports. It is more complex to sniff the wireless.

BigFatCat gravatar imageBigFatCat ( 2022-03-14 19:42:12 +0000 )edit

Hi, Thanks for reply. we are sure that the printer communicates over port 9100.Its Barcode printers Printronix T8304 Model with Ethernet port. We keep the Wireshark in server to capture the data on port 9100.The trigger for printing from other system to the printer.

pravinpednekar gravatar imagepravinpednekar ( 2022-03-15 13:14:42 +0000 )edit

We keep the Wireshark in server to capture the data on port 9100.

Is that server used as a printer spooler?

The trigger for printing from other system to the printer.

So direct communication between the other system and the printer? Thus no traffic via the server you did the capture.

André gravatar imageAndré ( 2022-03-15 16:40:59 +0000 )edit

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Asked: 2022-03-12 08:43:50 +0000

Seen: 689 times

Last updated: Mar 15 '22