How to Set Up a Split Bitcoin Wallet in Qubes

What is a “Split” Bitcoin Wallet?

A “split” bitcoin wallet is a strategy of protecting your bitcoin by having your wallet split into an offline “cold storage” wallet and an online “watching only” wallet.

A “Watching” Wallet and a “Cold” Wallet

  1. Create a Debian 8 backports template using the Qubes VM Manager or running qvm-clone debian-8 debian-8-backports in dom0.

  2. Add backports to the sources for the new template by opening a terminal in the new template, run sudo vi /etc/apt/sources.list and add deb http://http.debian.net/debian jessie-backports main.

    (If you are new to vi text editing, type i to be able to edit, and when done editing press ESC then type :x and press ENTER.)

  3. Update source list: sudo apt-get update.

  4. Install electrum from backports: sudo apt-get -t jessie-backports install electrum.

  5. shut down your debian-8-backports template

  6. create an offline-bitcoin qube based on debian-8-backports using the Qubes VM Manager or running qvm-create -t debian-8-backports -l black offline-bitcoin and qvm-prefs -s offline-bitcoin netvm none in dom0.

  7. follow the electrum documentation in creating an offline wallet

  8. create a watching-bitcoin qubes based on debian-8-backports connecting to the internet how ever you prefer using the Qubes VM Manager or running for example qvm-create -t debian-8-backports -l green watching-bitcoin and qvm-prefs -s watching-bitcoin netvm sys-whonix in dom0.

  9. follow the electrum documentation in creating an online watching-only wallet

Important Notes

  • The private keys (xpriv) should never be moved outside of offline-bitcoin.
  • For copying out the public keys (xpub), Qubes provides two secure, convenient methods: the inter-VM clipboard and inter-VM file copy tools. Compared to traditional physically air-gapped machines, these tools makes it very easy to copy out public keys.