OT: strange network problem

[borissh1983 at gmail.com]

On Monday, 10 January 2022 19:30:55 IST Erez D wrote:
> I've encountered a network problem
> 
> i have a mac and a win10 machine connected to a 4 port Gbit wifi6 AP
> (switch mode).
> a third eth from the AP goes to the router which is also a DHCP server
> 
> everything works well until the mac goes to sleep.
> when the mac goes to sleep, the win10 machine looses it's ip address
> which becomes a 169. address
> 
> as soon as i wake the mac up, the win machine regain a valid 10.0.0.x ip
> 
> i tried to replace the AP with a 4 port switch and got same results
> 
> 
> any idea ?
> 

IP in the  169.254.0.0/16 range is related to bonjour protocol , it is a link local communication.

your windows would move to a bonjur ip in many cases but most common that can happen if your machine has a bonjour service enabled and an Ethernet card with dhcp that can not get an ip from the router.

1. Check if when the mac is running your windows machine got it's ip from the mac and not from the router. in some cases mac can have dhcpd running on it, if that is the case you should disable it if you do not need it.
2. Check if homegroup is enabled on win10, if it is disable it (by version 1803 it is no longer active by default, but you could have hacked to enable it).