When preparing for the digital apocalypse, it is important to know the capabilities and limitations of your hardware and software. Remember, the point of the exercise is to be prepared for a no or limited Internet situation.
Set up a test network
It is important to have at least two routers on hand. One for production and a backup. I like to configure my network with the 10.0.0.x subnet with addresses 100-254 for the DHCP Pool. I’ll do a more specific post about configuring your network soon. What is important for now is that you know how to configure your router for networking WITHOUT having access to the Internet. Factory reset your router and set it up without connecting the WAN port to the Internet. Checking for Internet connectivity is often the first thing a router will do out of the box. Sometimes the setup process can be difficult to complete without Internet access. Take the time now to figure out the process and document it well. You won’t be able to Google “set up Netgear router without Internet” if you don’t have Internet.
Take good notes
Again, documentation is key. Take good notes either digitally (to print later) or hand write them in a notebook. Printing out pertinent sections of hardware manuals and how-to articles is also a great method of documentation. Not only is this important because you may not remember every detail yourself, someone else may need to take the reigns and configure your hardware using your notes.
Factory reset all the things
Factory reset your routers and switches and set them up from scratch without Internet access. Wipe the hard disks on any computers that you are using in your test environment and re-install the operating system without connecting. Using Windows? find out if all the hardware works out of the box without using Windows Update to get all the necessary drivers. Do you plan on having Apple hardware and software as part of your plan? They can present some unique challenges to an exercise like ours. Take good notes on any quirks you notice or workarounds you have to employ.
The “Cold Spare”
A cold spare refers to any computing component, equipment or device that requires manual configuration and adjustment in the event of issues or total failure. It requires the suspension of normal computer/system operations until the component is repaired and/or replaced.
technopedia.com
More succinctly put, a cold spare is a backup piece of hardware that can be swapped out for a failed device. Get your router set up the way you want. Get your DHCP reservations configured, set up your SSID and PSK, etc. Then configure another router exactly the same way. Try swapping one for the other and see what happens. Plan for total self sufficiency… The scenario we are preparing for doesn’t include Amazon Prime delivery of a new router or switch. This goes for servers, access points, whatever. If you only have one of something, you may as well not have it at all.
Freeze your software versions
Under normal circumstances, it is a good idea to keep software and firmware up to date on all devices. In our case, however, we want to find software, drivers, operating system installers, etc. that we can confirm to work without Internet access. For example, you wouldn’t want to do a factory reset on your router, configure and test it, then upgrade the firmware before storing it away for later use. There may be unexpected changes that can cause problems in the future. More on this later in another post.