This is strange, I am surely missing something
I have openhabian running on a rasperry pi 3. I am using my win10 laptop and I see that when I browse http://openhabianpi:8080 with any browser, it works
openhabianpi is the hostname of the raspberry pi. I have not touched my win10 hosts file, I have not updated the DNS with this name but it works with all my browsers, IE, firefox and chrome.
How is that possible ?
opehabian
win10
browser win10
You might try openhabianpi.local:8080 I’ve found that works best.
Windows supports a non dns standard that allows machines to broadcast their hostname to other windows machines to find it by name. Linux machines with samba will also implement this standard. This allow machines to find each other by hostname without dns.
That is why you can use openhabianpi in the url but nslookup didn’t return anything.
If your machine is using DHCP to get an IP from the router, it is possible that the router is taking the hostname from the DHCP request and filling its internal DNS with that.
My FritzBox does that 
Is there any way I can control that ? what is the protocol’s name ? I have installed a second instance of openhab in another raspberry to play around but of course the hostname resolves to the first one
Everything is in one subnet so no request to a router should be sent
Change the hostname on the second rpi and it will advertise a different name. All your machines should have a different hostname anyway.
It’s built into the operating system so I don’t think there is anything you can do about it. Maybe there is some registry setting you can use to turn it off. But the correct solution is to assign different host names to all of your computers. Or use IP addresses instead of hostnames.
Unless you assign static IP addresses, when the machine starts up it will ask the router to give it it’s network configuration. Being in the same subnet is not relevant.
Do you know the name of the protocol ?
Yes but i am not talking about a boot up. The router routes on ip addresses (not on hostnames) and it is only used when you are trying to talk to another subnet. That is why I am saying this is probably not relevant. This is clearly my PC (browser) that can route directly to the raspberry there is no router involved and clearly it is not via DNS or hosts file so your assumption it is a windows protocol sounds plausible
If I did I editor have answered the chest time you asked. But a search for “windows protocol advertise hostname” indicates it’s NetBIOS.
Bootup is when the RPi gets its IP address during dhcp. This is when the RPi will tell the dhcp server what is hostname is and thus the dhcp server will associate that IP with that hostname.
If you look at the dhcp table on your router, you will likely see some of the entries will include the hostname.
