A few days ago I went to check out my Skyaware and it was not working. None of the other APPS I have installed were showing working either on my desktop computer. Then I discovered that the IP address of the Pi had changed by one number. If I can recall I had this a long time ago. Has anyone else experienced this?
I presume you have the IP address allocated by DHCP. Have you added a reservation for the address? It sounds very much as if the lease on the address expired and it requested a new address but the old address had not yet been released and so it allocated the next one in the sequence. I have seen this before when there is no specific reservation set. If you did have a reservation set, then it looks like a bug in your DHCP server. Probably better to set a static address outside of the DHCP range.
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I normally dont mess with IP addresses.
That’s probably why you’re having this problem. I always go into my router’s setup page in a browser, find the DHCP-assigned local IP address of my Pi, and set it as a static IP so it will never change to prevent the very issue that you’re having now.
Regarding the other apps I assume you may mean VirtualRadarServer) you need to change their settings to point to the new local IP of your Pi. This goes back to the basics about how DHCP leased addressing works: addresses can change from time to time and to prevent that they should be made static.
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That I already have completed. What I did was go into my routers settings and checked all the connected devices and noticed the Piaware device IP changed from 000.168.1.17 to 000.168.1.18. I went into the pges shortcuts and changed the ip addresses and back in buiness. I will soon look into the DHCP settings. But the other Pi’s I have running for HFDL and ACARS did not change their IP addresses. They are still the same.
In your router reserve an IP address for a specific mac address. That way each device (mac address) will have its own IP address via DHCP.
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The fact that other devices’ addresses have not changed is a red herring. Don’t get hung up on that.
DHCP stand for “Dynamic Host Configuration Protocol”. It means that a device on the network is designated to dole out IP addresses to other devices. Often, the DHCP “server” will be your internet router/modem, but not always.
When a computer connects to a network and is configured to use DHCP, it broadcasts a request for configuration. The DHCP server responds with an IP address assignment (“lease”), gateway address, broadcast address, and DNS server addresses. These are linked to the computer’s “unique identifier”, or MAC address.
That address is assigned to that computer for a predefined period of time. Eventually, the lease will timeout and the computer will ask the DHCP server to renew the lease. Normally, this all happens in the background and you would never notice it.
The DHCP server defaults to renewing the lease with the same address in most cases.
But - it is possible that a particular computer’s lease could expire while it was temporarily disconnected from the network - either physically or do to a reboot or lockup - and while that address was “available”, a different computer could request an address (cell phone, smart TV, whatever), and be given the other computer’s old address. In that case, when the original computer reconnects it will be given a new address and happily use that.
This is all by design and works perfectly well. The only time it falls down is when you are accessing your computers by their IP address.
As others have mentioned, most DHCP servers include the ability to create a “reservation”, so that a specific address is only ever assigned to a specific MAC address. Alternatively, you can assign a “static” IP address on the device, by entering all of the address information manually. Static addresses on a DHCP network will work, but they require a degree of care - you probably should know what you are doing, so that you don’t manually assign an address that the DHCP server is trying to give to a different computer.
Remember that each device’s relationship with the DHCP server is separate from every other device’s. So just because one device did (or didn’t do) something, it doesn’t follow that others should (or shouldn’t) have done the same thing.
For the future, if you are going to have multiple computers with services that communicate with one another on your network, you are going to want to either have those computers stay put on the network (either reserved or static IP addresses).
On my personal network, I have it configured to use static addresses for my servers and printers, and DHCP for everything else. My DHCP server is set to assign addresses between 192.168.0.101 and 192.168.0.254 to laptops, cell phones, smart TVs, etc, and I use 192.168.0.2 through 192.168.0.100 for static addresses for things like my email server, web server, pihole server, laser printer, PiAware, FlightFeeder, and various other projects.
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