Setup:
Multiple PC’s in the office. Multiple Switches. Router & Modem for internet connecting to cable.
Having a strange network issue where we’ll lose internet & network connections simultaneously.
Something is causing the PC’s to lose their IP addresses and disables their ability to access any shared folders, servers & internet.
Rebooting the Router/modem does no good.
Rebooting PC’s does no good.
Rebooting switches & hubs on the network seems to temporarily solve the problem.
Rebooting the main switch seems to temporarily fix it. It’s random. It may solve the issue for several minutes to several days to weeks. Rebooting one of the smaller adjacent switches doesn’t seem to solve the problem.
The final diagnosis seems to be a bad switch/hub on the network. For whatever reason, it’s sending out bad signals and disrupting the connection off between the router & modem and also releasing all the DHCP addresses assigned to all PC’s & workstations.
One clue to watch for in terms of knowing/diagnosing which switch/hub it may be is to recall which network subset first went down.
The first section of the network that went down is a clue to which switch is causing the disruption throughout the entire network of switches & hubs.