what is the safest/easiest way to sync an offline desktop wallet? i like the idea of signing transactions on the offline pc, then transferring them via USB or similar medium and broadcasting from a pc that connects to the internet.
naturally, once you push a transaction or two, you need to sync the wallet, otherwise it will try to sign transactions using invalid inputs. where can i safely download block data, and what's the proper way to add it to my wallet directory so that it can sync past my latest transactions?
thanks!
You don't have to. What do you mean with "it will try to sign transactions using invalid inputs"?
as you confirmed below, the offline wallet doesn't know which inputs are spendable. e.g. the wallet tries to spend UTXOs that were already spent because it is not synced...
You create transactions in a watch-only connected to the internet wallet, only use the offline wallet to sign the transaction and then broadcast the signed transaction in a connected device. The offline wallet doesn't know which inputs are spendable in the wallet because it doesn't have to be ever connected to the internet.
this is the piece i was missing. i'll try out using a watch-only wallet. it didn't occur to me that a watch-only wallet could construct the transactions. sounds easy enough, thanks.
I myself, have a bootable image that has Electrum installed and my wallet is showing a balance of 0 BTC. Are you saying that you always sync your offline wallet and create the transaction from there? Because this takes away the whole purpose of using a cold-storage wallet.
no. that was the whole point of my post -- how to get up-to-date UTXO data without connecting the offline pc. why would i make this thread if i were just connecting the "offline" pc to the internet? LOL...
i guess maybe that line of thinking makes sense for electrum, where syncing
means connecting to a trusted server. with a full node, the database directory should include block data, current chainstate, UTXO set. i was asking how i could extract that block data from a synced node's directory and transfer it via flash drive to the offline wallet. i still don't see why that should be a problem, though i'm just not clear on the specifics of what should be transferred.
my thinking was that transferring signed transactions via flash drive expose it to similar attack vectors (being air-gapped is irrelevant there), so no real security loss. i'm not sure i understand how that "takes away the whole purpose of using a cold-storage wallet" unless you're telling me that the only way to get block data is to literally connect to the internet.