The CG3000 will reboot itself. The power LED will blink, then stabilize. Wait an additional 2 minutes for the DOCSIS downstream/upstream channels to re-lock.
To address these challenges, ISPs and device manufacturers can: kaon cg3000 firmware update
Do not turn off the router or disconnect the Ethernet cable during the update process. Troubleshooting & Security Tips cg3000 (docsis 3.1) - KAON MEDIA The CG3000 will reboot itself
To recap: