Multisig wallet: Windows + Headless linux

[EcuaMobi]

I'm trying to create a 2-of-3 multi-signature wallet with Electrum consisting of:

• My main Windows machine
• A headless Linux machine
• An extra paper-backed-up seed created on an offline machine

(The last one is optional, it could be a 2-of-2 wallet)

I already installed the Electrum wallet on the headless Linux machine and am able to create a regular wallet and use it via command line. How can I create a multisig wallet here? I mean how can I replicate this functionality via command line?


I see the 'create' command just have the options --verbose, --portable, --wallet (path) and --offline. 'createmultisig' just creates a single multisig address, not a wallet. Is this possible at all? I can't find a definite answer in the docs.

If this is not possible I could just grab the xpubkey from the Linux machine and use it to create the wallet on the Windows machine. In this case can I then sign the (multisig) transactions on the Linux machine somehow, effectively just using the headless Linux as a 2FA?

[1714190048]

1714190048

[ThomasV]

yes, you have to use the GUI; there is no command line way to create a multisig wallet in the current version.

[EcuaMobi]

You can't import a standard wallet XPUB (or paper wallet) into a multisig wallet (as you implied, with importing your headless linux XPUB into the Windows multisig) - since your Linux wallet (or paper wallet) won't be multisig and won't be able to sign transactions for an address it didn't generate (because you created the Linux wallet without your Windows XPUB).

For multisig to work, ALL wallets allowed to sign a transaction have to be created with the XPUB of the other signatory wallets.  

In a 2-2 arrangement:  
- A has to have XPUB of B
- B has to have XPUB of A

In a 2-3 arrangement:
- A has to have XPUB of B and C
- B has to have XPUB of A and C
- C has to have XPUB of A and B

By doing this, all the wallets that are part of the multisig arrangement will generate the exact same bitcoin addresses.  This is how you can check if your multisig system will work.

With Electrum, to my knowledge, you have to use the GUI windows to create multisig wallets - ie. I haven't seen any command line to create them.

I was just wondering about using Linux's pubkey on the Windows UI, thanks for clearing that out.

I hope it will be possible to create a multisig wallet via command line in the future, that would be a nice 2FA system.