I'm trying to learn more about doing multisig transactions.
The examples I've seen show the signing of the transaction with 2-of-3, or 3-of-3, where the signatures are added, essentially, at the same time, and same place.
I'm wondering how does one, using rpc or cli, perform a multisig spend from physically separate machines?
How does a signer know that there is a transaction that he/she needs to sign?
Can a 2-of-3 transaction, that initially only contains 1 signature be broadcast, then updated by the 2nd or 3rd signatory?