The Backup Laptop: What Goes on It, How It Is Stored, and the Faraday Case It Lives In

Scans of every document you would need to prove who you are and what you own: IDs, passports, birth and marriage certificates, deeds, titles, insurance policies, medical records and prescriptions, tax returns, and photos of every room and valuable for an insurance claim. A contact list and an account list. Offline maps of your region. Reference: the PDFs from this site, the book, repair manuals for the generator, the well pump and the vehicles, first aid references. Then the things that keep people sane: music, movies, books, games for the kids. All of it in plain folders you can find in the dark.

Unplug it, power it off, and seal it in a Faraday bag with the closure fully shut. The bag is a conductive shell that carries the pulse around the outside; a gap, a cable through the opening, or a device left plugged into the wall defeats it. A laptop that is off and unplugged in a sealed bag is about as safe as electronics get; a metal ammo can with the lid taped and the laptop insulated from the walls does the same job for less. It stays in the bag until you need it.

I use the Faraday Defense JACKET Pro Cordura laptop bag: a laptop-sized shielded liner inside a tough Cordura shell with a magnetic roll closure that seals every time. It blocks EMP, radio and cellular, so it also works as a privacy bag for a phone or a hard drive. A cheaper option that works is a steel ammo can with the laptop wrapped in a towel so it touches no metal and the lid sealed; it is just heavier and uglier.

The same list as the laptop, in the apps that open offline: the document scans in Files, offline maps downloaded for your region in a maps app, PDFs of the field guides and manuals in Books, medical references, the contact list, and enough movies, music and books to get a family through a week with no signal. Download everything while you have internet, open each one once to be sure it is stored on the device and not in the cloud, then power it off and put it in the bag with its charging cable.

Yes, and on the phone and the tablet too. Download the map tiles for your county and every route you would drive out, at street level, from whichever map app you use; most let you save an area for offline use. Add topographic maps for the land around you and a PDF of the state road atlas. Then print the ones that matter, because the whole point of the backup laptop is that something went wrong, and paper does not need a charge.

Charge it to 50 to 80 percent, shut it down fully (not sleep), and keep it cool and dry; a lithium battery stored full or empty in heat ages fastest. Every six months take it out, boot it, install any updates while you have internet, refresh the files, charge it back to 50 to 80 percent, shut it down and reseal it. A laptop treated this way boots in five years. One left at zero in a hot attic will not.

Yes, because it holds every document that makes identity theft easy, and a stored laptop is the easiest thing in the house to carry out the door. Turn on full-disk encryption (FileVault on a Mac, BitLocker or device encryption on Windows), set a strong login password, and write that password on paper in the household logbook or a sealed envelope, because a locked backup with a forgotten password is a paperweight. Keep a second copy of the most important files on an encrypted drive in another building.