Blank OTA vs Arduino OTA

Hello I am currently using Blynk but want to use OTA. I can’t use Blynk OTA in my scenario so I want to use Arduino OTA.

Here is the reason:
I have multiple devices that works as one unit, they all have the same authorization code. Therefore I can’t use blink OTA because it will upload the sketch to all devices.

I know Arduino OTA uses IP adresse, and I have managed to set it up but when I then use OTA to upload the Blynk sketch I cant use OTA anymore. It seems like Blynk overwrites OTA sketch.

Does anyone has any suggestions?

Btw if there is a way to get all the information from different devices at the same dashboard it would make it possible for me to use Blink OTA.

Because I have one device at one location measuring temperature and other things, another device in another location measuring something else, but I don’t want to switch from one dashboard to another to see the values.

Blynk only allows an Auth token to be used on one device at a time. If you have two devices sharing the same Auth token then when the second device connects to Blynk, the first will be kicked-off.

You’re doing something wrong with your Arduino OTA then. Blynk and Arduino OTA work well together, provided you write your code correctly.

Automations, the HTTP(S) API and Node-Red are all possible solutions…


That is not true. Both devices is working fine at the same time. However they dont use the same virtual pins.
As you can see on the screen shot both devices is online and running.

I will try it again then and if it still doesn’t work I will share it.

Never heard of it before but will try look into it.

Okay I might have followed the wrong guide.
I followed this one with basicOTA

Now I found an updated one.
Updated one:

I will try that later.

That’s interesting.
Until recently it workled the way I described before, but it seems that there’s been a change and now two devices with the same auth token are tolerated.
However, it wouldn’t surprise me if it reverts back to how it was, which would break your current setup.

There are so many things wrong with that tutorial that its difficult to know where to start!

The second tutorial is better, and you’ll no doubt see why you can only do one OTA upload when you follow the first tutorial. However, neither make any mention of installing Python 2.7 to enable OTA ports to be visible, or any mention of the fact that virtual network port discovery uses the Bonjour service.


You completely lost me on this one. What do you mean with OTA ports and Bonjour service?
Is it for using OTA through the internet?
Because as I understand it, the guide only make it possible to do it through WiFi locally.

For the Arduino IDE to see the OTA devices on your local network, your computer needs Python 2.7 installed, and the devices are found using the Bonjour discovery service, which needs to be running as a service on your computer.
In the second video, the guy is having issues with these virtual network ports not showing-up on his PC unless he restarts the IDE. This is caused by a Bonjour discovery issue.

Arduino IDE can only be used on devices connected to your local network, unlike Blynk.Air OTA, which can be used to update devices anywhere in the world.


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Okay but it can work without these two things, you just need to restart IDE every time?

Without the Bonjour service running the virtual network ports will never appear. The Bonjour service will most likely be installed and running by default on your PC, but it’s always good to check.
If you find a proper Arduino OTA tutorial rather than watching amateur YouTube videos it will guide you through the Python 2.7 installation.


Okay what about having a single dashboard?
I looked a little into that, as I understand the only way is to have a master slave setup.
So you have one master device connected to Blynk and several devices connected to the master.
But I can’t see the point of doing that in my case because then I would only be able to use Blynk OTA for the master device.

Im leaning towards having multiple Blynk device with different dashboards and live with the hassle of switching between dashboards.

I’m not sure which of the potential solutions you’re referring to with this scenario, so it’s difficult to comment.

I don’t think that running the same Auth token on multiple devices is sustainable, as it could easily stop working if Blynk revert back to having server checks that automatically disallow this.
As I’ve said, there are multiple ways to show the data on one dashboard, and several of those allow OTA on all devices, but your comments are to vague to have a proper discussion about the pros and cons of each.

I’ve seen comments from Blynk where they hint at a solution that will be released soon, which will allow data from multiple devices to be displayed on one dashboard, but I don’t know the details, release date, or whether it will be restricted to certain subscription types only.


I’m confused when you say there are multiple ways to show data on one dashboard. Do you mean there are other solutions than using Blynk or do you mean multiple ways to get it working with Blynk?

As I said before….

Automations would allow Blynk.Air updates in all circumstances.
The HTTP(S) API could be implemented multiple ways, but if you take the approach used in the examples I linked then Blynk.Air would work.
You could implement Node-Red in multiple ways, but the most sensible one would not allow Blynk.Air to be used, so you’d need to use Arduino OTA, which is the approach I use.


No. I think @Henrik9979 doesn’t use one token, but one sketch?

The release of this feature is planned for the end of June.

I did a test today, using the same token on two different devices, one updating datastream V0 and the other updating V1 with their uptimes.
Both devices are able to be connected at the same time, and both devices are incrementing the corresponding datastream with their own uptime values at the same time…

so something has changed at your end, and when a second device connects with the same auth token the first one isn’t disconnected now.


Hopefully they will keep it that way because its a pretty neat feature.

It just removed the possibility to use Blynk OTA.
But then Arduino OTA can be a work around.
But Arduino OTA could not work through the internet right?

The problem is that it allows people to use more devices than their Blynk subscription allows. It also means that you don’t get proper on/offline notifications and statuses for your devices. The whole ethos if Bklynk has always been is that it’s one auth token per device. This auth token validates the device against the server and links it to your account and the dashboard for that device.

I’ve already made that clear, but it seems that you aren’t reading what I write…


Yeah Sorry I saw that shortly after I send my response.

Im looking into Node-Red but at the moment I can’t wrap my head around if it will fulfill my needs or it also will have some limitations.

I sort of understand how it works but also feel likes it’s running on magic.

That was the same feeling I had first time trying to get blynk to work, I needed the very basic understanding of how a pin from a ESP32 could send data to a webpage.
I understand that now.

But Node-Red is still mysterious. I’m even not sure what it is??? Is it a sketch that is uploaded to the ESP which you access from a web browser?

Most of the YouTube videos explaining how to make it work with blynk is in different languages I don’t understand.

So for now I think I leave it here, using different devices with different dashboards to make use of Blynk Air OTA and hopefully blynk will implement and multi dashboard solutions later.

Once again, you’ve not read the links I’ve provided!

Me too, as providing information to you is obviously a waste of time.


I did but that’s quite a mouthful to get through and I know it’s something that won’t take me 20 minutes to get working the first time.

Because I would need to make a simple test project first to make sure I get it to work, then play around with it and understand what the parameters do. After that I would need to reconfigure my project so it works with Blynk Air OTA and implement Node-Red.

So when I have a whole weekend with nothing to do I might try.