# Openzwave and USB stick (un)plugged in real time
**URL:** https://discourse.nodered.org/t/openzwave-and-usb-stick-un-plugged-in-real-time/46226
**Category:** General
**Created:** [25 May 2021 18:00 UTC](https://discourse.nodered.org/t/openzwave-and-usb-stick-un-plugged-in-real-time/46226 "2021-05-25T18:00:13Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@Mamonetti](https://discourse.nodered.org/u/Mamonetti)
#### Post date: [25 May 2021 18:00 UTC](https://discourse.nodered.org/t/openzwave-and-usb-stick-un-plugged-in-real-time/46226/1 "2021-05-25T18:00:13Z")
Is there any way to make openzwave (node-red-contrib-openzwave) go back to life when you unplug the USB stick and plug it again without having to restart nodered?
I don't know if it has to do with me having multiple Z-Wave nodes at the same time using the same controller, but even though I know it's moved from /dev/ttyACM0 to /dev/ttyACM1 (probably because the openzwave library kept the port in use) and I reconfigure the node to use the new device, it still doesn't work.
I've also tried to go a bit further after that by unplugging it and plugging it again to see if the library had already released /dev/ttyACM0 but it hadn't and I keep getting /dev/ttyACM1 again. No need to say that it doesn't work this way.
Regards
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### Author:  [@ghayne](https://discourse.nodered.org/u/ghayne)
#### Post date: [25 May 2021 18:48 UTC](https://discourse.nodered.org/t/openzwave-and-usb-stick-un-plugged-in-real-time/46226/2 "2021-05-25T18:48:45Z")
Why do you need to unplug/plug the USB stick?
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### Author:  [@Mamonetti](https://discourse.nodered.org/u/Mamonetti)
#### Post date: [26 May 2021 07:47 UTC](https://discourse.nodered.org/t/openzwave-and-usb-stick-un-plugged-in-real-time/46226/3 "2021-05-26T07:47:18Z")
Let's say I have a client without enough experience on using the command line (ssh and this stuff) and I want him to identify the set of nodeids of the devices from a network. Considering I can't go there (covid..), the idea is to prepare an image with a web server that shows the contents of /dev and /home/pi/.node-red (in addition to the Node-Red interface, of course), allowing him to do something like this:
- Start from scratch will the list of paired nodes empty (brand new stick).
- Identify the serial port assigned to the stick (normally /dev/ttyACM0).
- Configure the _Z-Wave IN_ node in Node-Red.
- One by one, unplug the stick, pair a device, plug the stick again and force a writeConfig operation in order to identify which nodeid has been assigned to this device (look at the xml cache file that has just been updated).
With this I will send him a flow that will load a json config file with the filter of which set of [nodeid,cmdclass,instance,cmdidx] will be sent to the platform, among other things.
If I have to, I'll send him a small guide on how connecting with putty and stop/start the Node-Red service, but I'd like to avoid that.
Regards
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### Author:  [@system](https://discourse.nodered.org/u/system)
#### Post date: [25 July 2021 07:48 UTC](https://discourse.nodered.org/t/openzwave-and-usb-stick-un-plugged-in-real-time/46226/4 "2021-07-25T07:48:12Z")
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