Is safe running bitcoins with the same wallet on more computers simultaneously?

[Aleš Janda]

Hi,

I would like to use bitcoins but I'm using more than one computer. Can I use just one wallet on all computers (by copying settings)? Or it isn't possible?

What happened if someone send me money and bitcoin client run on more computers? What happened if I send money to anyone from one of clients? Will it be synchronized automatically?

Maybe it's a simple quetsion but I didn't find answer to this.
Thanks.

[BitLex]

i've never tried it myself and wouldn't recommend to,
in no way it's "safe", i guess it will cause some trouble sooner or later.

if you just want to use your wallet (spend/receive coins) on multiple machines, there's ways to make it portable (i guess, also not tried yet).

if you want to generate on multiple machines, that's possible by using a single client/wallet and multiple miners (GPU, CPU) running on the same, or multiple remote machines.

[FreeMoney]

I'm interested in hearing the problems with this. The current version generates a pool of 100 address, but are these used for receiving change? Maybe there could be an option for generating more than 100 addresses, and also for seeing how many you have left?

Is there some other type of problem I'm overlooking?

[BitLex]

the option to generate more addresses to the keypool already exists

Code:

# bitcoin.conf

# Pre-generate this many public/private key pairs, so wallet backups will be valid for
# both prior transactions and several dozen future transactions.
keypool=100

but as far as i understand, it's supposed to keep backups valid (for some time), not to sync multiple wallets.
i have no idea how that would work in the long term.

[satoshi]

Will it be synchronized automatically?

Very much not.  Using multiple copies of wallet.dat is not recommended or supported, in fact all of Bitcoin is designed to defeat that.  Both copies will get screwed up.

If you're trying to consolidate your generated coins into one wallet, a better solution now is to run getwork miners on the additional systems.  jgarzik has a CPU miner, and it supports tcatm's 4-way SSE2, so on Windows it's up to twice as fast as the built-in SHA if you have an AMD or recent Intel (core 3, 5 or 7).

New demonstration CPU miner available:
http://bitcointalk.org/index.php?topic=1925.0

[Aleš Janda]

Thank you very much for your reply. If more instances of running program with the same wallet isn't possible, I think it should be documented.

But OK, so I can other scenario:
I have 2 computers, one at home, one at work. I'm running bitcoin at home, then I shut it down, go to work, start running bitcoin there, with the same wallet. Then shut down, go to home, start bitcoin at home and so on. BUT: I don't synchronize files (~/.bitcoin). So I don't run more instances of the same wallet but I don't synchronize current state.

It's this possible? Will be synchronized sent and received payments or are there other problems? Or rather I should use two different wallets, one at home and one at work?
Thanks

[BitLex]

again, i wouldn't recommend that,
either use a portable version on a thumb-drive,
or simply a https://www.mybitcoin.com/ or https://mtgox.com/ account.

keep your wallet safe at any time, or risk to lose all your money!

[bencoder]

Thank you very much for your reply. If more instances of running program with the same wallet isn't possible, I think it should be documented.

But OK, so I can other scenario:
I have 2 computers, one at home, one at work. I'm running bitcoin at home, then I shut it down, go to work, start running bitcoin there, with the same wallet. Then shut down, go to home, start bitcoin at home and so on. BUT: I don't synchronize files (~/.bitcoin). So I don't run more instances of the same wallet but I don't synchronize current state.

It's this possible? Will be synchronized sent and received payments or are there other problems? Or rather I should use two different wallets, one at home and one at work?
Thanks

They won't be synchronised. It might synchronise for a little while until your 100 saved addresses are used up, but after that you'll be using different addresses on each machine, so it will become unsynchronised... so if you make a payment you'll get the change on one machine but you wont get it synchronised on the other, you'll just see the loss of money.

I am curious if/how it would cause any problems beyond a forking of the wallet though.

[Aleš Janda]

Ok, thank you very much. It's a pity but I savvy it. Linked services I'll try.
So thanks again.