Using and connecting to multiple duets?

[EducatingSavvas]

Hiya - this is a general observation that I wanted to share. I'd be curious to know what people experience are for what is a rare problem. I have recently set up two workbees with my own self-built CNC controllers in an educational setting. I am using duet 2 wifi's with access points sending gcode from a single computer. I had a mishap when one wifi connection was disrupted and the computer automatically connected to the second however the browser didn't refresh to reveal the name of the controller I was connected too - named in the top left corner. I went to move one machine while the other was processing gcode and this resulted in the spindle turning off. The simple solution is to get a second computer and to make sure the login details are not swapped. But I'm wondering if it's possible and worth automatically refreshing the browser when reconnecting to the wifi network so the correction duet controller name is always displayed in the top left corner.

[jens55]

I use a single computer to slice (Cura) for three printers. Duet 2, Duet 3 and a Marlin based printer (CR-10). As long as I make sure that the slicer sends the model to the right printer, nothing untoward has ever happened. Yes, there have been incidents of the connection dropping and there have been incidents of me needing to refresh a web page but I have never encountered a situation like what you are (I think) experiencing. Each printer has it's own fixed IP address and I see no reason/way how this can magically change. Further, even if somehow the web page from a different printer showed up (which would show the different printer name in the left top), it doesn't do anything to the print since the print is stored locally on the printer, independent of the web display.
In other words, I can slice one model, send the model to the printer, slice another model and send it to another printer, slice a third model and send it to the third printer and do all of that on a single computer even without any Duet (or Marlin) web page being open to monitor anything. Each printer, once the sliced model has been downloaded to it, will independently continue until it's respective model has finished printing.
Maybe I am not understanding the question correctly ?

[jay_s_uk]

@jens55 i think @EducatingSavvas is using the machines in access point mode?

[droftarts]

@educatingsavvas I’d guess that you have set up each Duet access point with different SSIDs, but the same IP address and/or machine name, so when one Duet dropped out, the browser reconnected to the other Duet, and established a connection on the same IP address to the new machine.

See https://duet3d.dozuki.com/Wiki/M589

Change the IP address of one of them, using M589 with i parameter. Send M589 on its own to see current configuration.

Ian

[EducatingSavvas]

@droftarts Thanks for that - I did wonder if having the same IP address would cause issues. I have had to change my workflow to include changing the pendant address but that is a small price to avoid this problem. I will test it out over the next week or so and report back what I notice.

[EducatingSavvas]

@droftarts sorry this has taken me a while to reply too but using different IP addresses and moving between controllers on a single computer (changing wifi login using access points) doesn't result in the controller name updating in the browser without a manual browser refresh. This feels like a potential safety issue as the controller can still connect and commands accepted. Is there some g-code that can be placed into the config.g or daemon.g file which refreshes the browser after wifi reconnection?

[Phaedrux]

I think there is some work being done on better supporting multiple Duets on the same network.

[fcwilt]

@educatingsavvas

To verify you are using ACCESS POINT mode on your Duets?

If so may I ask why?

I have 5 printers running in CLIENT mode and have no problem controlling the desired printer.

Thanks.

Frederick

[EducatingSavvas]

@fcwilt Hi Frederick - the CNC machines are in an educational setting - the network is only accessible via user accounts login details, so using access points seemed a lot easier with multiple users. When using client mode with multiple printers - what happens if you write http://duet.local in the URL? Maybe I'll have to get IT in to work out a solution.

[fcwilt]

@educatingsavvas

Is everyone who can log on to the network authorized to use the printers?

Each of my printers has it's own dedicated IP address so you simply do something like http:\192.168.0.123, assuming that is an IP address assigned to one of the Duet boards.

Since I keep the computer I use for the printers up and running 24/7 the browse already has tabs opened for each printer, so I can just switch to the appropriate tab to work with a given printer.

You can assign a password to the Duet board but I have no idea how robust that is.

Access Points have security features which could limit who could connect to the printers.

Frederick

[jay_s_uk]

@educatingsavvas are you keeping the same name on all of them? Maybe change it in M550 which would force the use of a different .local name

[EducatingSavvas]

@fcwilt No they shouldn't, and students will need training before accessing. I may put a password as an additional failsafe. The issue I had was using one computer to operate two CNC controllers due to space limitations. I guess I could get a modem and create my own local network as an alternative.

@jay_s_uk Hi Jay hope you are well! No, the names are different but both can access http://duet.local.

[rjenkinsgb]

@educatingsavvas
Save their unique IP addresses as favourites instead of duet.local; the browser can never get confused then as it will fail to connect if that IP address does not exist on the network.

You can give each bookmark a unique name, as with my two Duet based machines:

[jay_s_uk]

@educatingsavvas yes, good thanks. Hope you are well too? That's odd that they will respond to duet.local when the name has been changed. Usually the M550 name drives the mDNS details https://docs.duet3d.com/en/User_manual/Machine_configuration/Networking#a-note-about-mdns-local-network-discovery

[EducatingSavvas]

@rjenkinsgb that works, thanks for that - so I'll have to write the IP addresses in the student workflow. Hopefully won't confuse them too much. @jay_s_uk Not bad, just busy as usual. It's strange but writing http://anything.local accesses the web controls.