I have a RaspberryPi which is going to act as the server for my Arduinos which are connected to the same network.
However, the RaspberryPi is unable to automatically connect to the Arduino. I have to hardcore each Arduino IP address into the server.
Is there anyway for my server to search the network and identify the arduino so it could be added into the server database automatically. Or the other way round, the arduino find the server ip and attempts to connect to it.
My server is running on node.js
If both the Rasbpi and the Arduino are connected to the same router, they are in the same subnet. You can let tell your server periodically scan the subnet ip range.
I am not familiar with node.js but here are some good starting points for network scanning:
https://www.npmjs.com/package/ip
https://github.com/jas-/node-libnmap
From your server install the latest nmap binary then expose that tool to node.js like so:
'$ npm install --save libnmap'
Then use the discover method available to find all connected devices per network interface.
var nmap = require('libnmap');
nmap.discover(function(err, devices) {
if (err) throw err;
console.log(JSON.stringify(devices));
});
I would use mDNS to find the Arduinos. The only requirement for the RPi is to be running Avahi, to have the appropriate multicast port open, and to have the mDNS resolver installed and configured. There are several Arduino libraries available that implement mDNS; a quick Google search finds a few.
Related
I created two Qt apps: one client and one server.
I use them to send some data for handle a remote device.
If I am in localhost I haven't issues about them, but when i search to connect them by internet i don't know how to find correct Ip server to connect Socket Client.
How i can find this ip node?
Is there a class to find It?
you cannot find it automatically, if this is what you're asking about.
In real life you would deploy your server on some publicly accessible host, give it a domain name (important part as your host can change the IP address at any time) and connect the client via the DNS domain.
However if you're just playing around and you want to show to the world that your app works, specifying the IP address of the server in your client code would be perfectly fine (assuming you're running both the server and the client in the same network).
In that case, if you're running mac/linux run the command ifconfig (or just ip depending on the distribution). On Windows you can run the command ipconfig. Both windows and linux will give you a similar output resembling this:
Pay attention to the network adapters. There can potentially be many of them. You may have some emulated adapters if you have docker or VMWare, you may have the wireless adapters if you have a WiFi card, and then the ethernet adapters if your computer can connect to the the internet with an ethernet cable. Each of these adapters specifies a different IPv4 address. You want to pick the one that is connected to the same network as your client. So for instance if both your server machine and your client running machine are connected to the same wifi, you pick the address from the Wireless LAN adapter
I have recently installed the CORE Network Emulator, and have already read the relevant parts of the the docs. CORE promises to be able to connect the virtual networks you create in it with physical once. However, I am having trouble connecting my virtual network to the physical one, which the RJ45 tool promises to do. From what I have read, in the CORE NetEm you can assign a network interface to the RJ45 tool, which then bridges your physical device to the network.
I have tried creating a basic topology, with one virtual host, a router, and then my computer with the RJ45 tool and I am trying to see if I can reach my computer from the host or vice versa with a ping command, but all I get is "network is unreachable."
Unfortunately, the CORE docs don't go into detail in how to use this tool and I wasn't able to find any other sources on the internet which have to do anything with it.
Here you can find the documenation: http://coreemu.github.io/core/usage.html#connecting-with-physical-networks
Does anyone have any experience with CORE and can help me out with this?
Many thanks!
The CORE RJ45 tool creates a Linux bridge between a virtual interface and a physical one.
Example: if you have node n1 linked to an RJ45 node assigned to eth0, after pressing "Start", on the underlying host you'll have a bridge with the n1:eth0 veth0 pair device and your host's eth0 device enslaved.
You'll need to configure routing between your virtual and physical networks. In the above example, suppose n1:eth0 is 10.0.0.1/24. When you plug a physical device into eth0, that device needs a route back to 10.0.0.1. That device may be on the same subnet, for example if it has the address 10.0.0.2/24. If your physical device has an address on a different subnet, you'll need to manually add a route to reach the 10.0.0.0/24 network, via the connecting interface.
I had the same problem. My CORE version is v.5.3.0 (20190615) on Ubuntu 18.04 LTS w/ Linux 5.0.0-37 generic on x86_64. Have OSPF v2, v3, Zegra, and IPForward correctly configured at r1, so that vpc1 can send and receive data successfully.
The RJ45 port of a built-in physical interface on the CORE host was mapped to a virtual endpoint for connecting the 2nd real computer, rpc 192.168.10.10/24 with a virtual switch sw1. Another virtual PC, vpc1 192.168.10.20/24 and a router r1 with 192.168.10.1/24 and 10.0.10.1/24 two interfaces.
Can ping from rpc to vpc1 and to r1 at 192.168.10.1 but not 10.0.10.1 or beyond. However, using the two-node tool or virtual terminal of vpc1, I can also traceroute and ping r1 and beyond.
The reason why the traffic of the real remote PC rpc could not be routed by r1 from 192.168.10.1 to 10.0.10.1 and back was because its WiFi was left on with the gateway configured to a FiOS router. You cannot have two gateways. Once the WiFi got turned off, the traceroute and ping can reach r1 and beyond.
This could also be the root cause of your problem.
Windows machine: After configuring on-board WiFi, I cannot access Arduino Yun board using arduino.local. However while configuring, I gave name of the board exactly arduino.
Linux (Ubuntu): However if I repeat same steps configuring WiFi in Ubuntu, I can access its webpanel using arduino.local in browser.
Any solution how can I access from a Windows machine. Or how to figure out IP address of the board to access its webpanel?
You should follow the instructions on their site very carefully.
Specifically:
NB: The Yún uses Bonjour services for auto-discovery on a wireless network. This service is not included with Windows by default. If you do not have Bonjour already installed, you can download the service from here. Additionally, you should make sure any anti-virus software is not blocking communication on port 5353.
I have some device in MIPS architecture, on this device unfortunately wasn't instal any server ssh, but telnet daemon is present. I try connect to this device in goal remote debbuging but I do not can connect. Also If I try test connect.
So it is possible to remote debugging in Qt trought Telnet ? Whether this function is only reserved for SSH server ?
This is my application setup.
I have written an application (in Qt ) which will run on a linux computer (Ubuntu). The application accepts requests from web app and sends them to a serial device that is connected to the computer. Also application will send back the response to web app as well. This linux computer is connected to internet via wifi router.
Now my question is, Is there a way (other than port forwarding in wifi router) that I can achieve this functionality. Using port forwarding I can ask the router to forward the requests coming for a particular port to my computer at a particular port and my application would be listening for that. But for that I would have to configure the router and I don't want to do that. Is there a way I can do that automatically?
Thanks,
DPatel
Your issue is traversing non-routable NAT addresses.
UPNP is an option: http://en.wikipedia.org/wiki/Universal_Plug_and_Play
It will automatically configure port forwarding.
There is a library out there called STUNT for this as well:
http://nutss.gforge.cis.cornell.edu/stunt.php