Establish D2 Series management session without COM port

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Hello everyone!
I need ideas to solve this question.

Is there the possibility of programming D2 series switches starting from factory configuration - that is, connecting to the RJ45 switch console port - using a PC that does not have a serial COM port?

I tried using a serial to USB converter connected to the PC usb port, but it didn't work.

Thank you in advance for any suggestions ;)
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Alice Grandi

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Posted 3 years ago

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Bharathiraja, Suresh, Employee

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Hi Alice,

What is the response from switch and PC when you connect the cable ?

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Alice Grandi

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Hi Suresh,
when I connect the switch to the PC using the RJ45 cable, RJ45 to DB9 connector and serial to usb converter it's just like the cable was disconnected.
If I try to establish a management session with PuTTY, as I usually do, the response is "Unable to open connection to COM1. Unable to open serial port".

Obviously I checked the RJ45 cable, RJ45 to DB9 connector and serial to usb converter and I am sure they are ok - I use them successfully to connect to B5 Series that do have serial console port, or D2 Series connected to a PC COM port.

The fact is that I have a Sony VAIO mini laptop that I would like to use to program D2 switches, as sometimes I need to do it outside my office; actually I can do it only if the switch has a serial console port, and using the serial to USB converter connected to one of the laptop USB ports.
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Bill Handler

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We've run into this before with a USB to Serial adapter.  We had seen where for no apparent reason, the COM port changes when it is plugged in.  We've also seen where an USB/Serial adapter will not work on a laptop even when the driver is loaded correctly.

When we see the message: "Unable to open connection to COM1. Unable to open serial port", that usually indicates an issue with the USB adapter.  Even when the console cable is not connected to a switch, so long as the USB adapter is talking to the computer correctly, the COM port should open.

I don't know what USB/Serial adapter you are using, but we have settled on the Tripp-Lite Keyspan USA-19hs.  These adapters seem to work on all of our different laptops.

I would look at the adapter first for this issue.

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Martin Flammia

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Think if you go to 'Control Panel', 'Device manager' and I think its under 'Ports (Coms & LPT)' (not able to look on the PC I'm currently using to check for you) you should be able to see what port your USB device is using - you can then use that in PUTTY.

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Matthew Hum, Principal Engineer, APAC

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USB-to-Serial adaptors will almost never be assigned the COM1-COM4 ports; those are reserved for physical ports as they have specific addresses and IRQ3 and IRQ4 reserved for them. They are generally assigned a higher COM port, 8-12.
One reason COM ports change is if a program has the COM port open that port will not be assigned. So if your USB port is loose and the USB-to-Serial adaptor has intermittent connection, and a terminal program has the port open, then the same adaptor will be assigned a new COM port.
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Being in a similar boat with Macs, I found, and have stared using a device called AirConsole.
Wireless/Bluetooth/Wired access. Impressive little boxes.