Why is there no Internet connection in Windows 7 after a long idle time of the PC?

Question

DHCP

Hello! There is a Windows S 2012 domain, there are ~ 30 workstations running Windows XP-8. The stations are divided among themselves into subnets by means of routers running OpenWRT. Stations go to the Internet using NAT through the central Linux gateway. Stations receive automatic settings for dhcp (dnsmasq) from routers. So, there is such a feature: when a PC is turned on after a night of inactivity, on some of them (randomly) a notification appears that the local network connection is limited, they say there is no Internet connection.
I go into the network connection details - everything is fine, all IP settings are received correctly. I ping the router of this subnet - there is no ping. I ping the central gateway - there is no ping. I turn off and on the adapter at the station through the context menu - everything starts working. It was noticed that the above happens on Windows 7 Pro SP1, and always on different ones, besides, this all happens both under the admin account and under the account of a limited user.
How to get rid of this nonsense?
Thank you for your help.

Answer 1

Do computers turn off or go into sleep mode?
Disable sleep mode