I tried to update this old thread…
I have had an ongoing and unclosed issue with top level Netgear support, where I had noticed large file copies through the night were getting aborted. Looking in the windows error log, I found DHCP NACK messages, meaning the DHCP server in the main router where cancelling the leases, at 12 hour intervals (was set to 24 hour leases).
Netgear provided several test software, which had the same bug, as well as a whole new unit. Same old. Disabled DHCP on that router, and used a DNS-323 as the DHCP master, and the issue went away.
This DHCP NACK seems to mess up any TCP sessions in progress, like backups, etc.
I am not sure how to find these message logs on non-Windows machines.
https://technet.microsoft.com/en-us/library/cc958935.aspx Description of DHCP states