Best Practices - Multibit (backup)

[SheHadMANHands]

Hello,

I'm comfortable with using the Multibit wallet client, so I was curious of any "best practices" for cold storage on USB sticks.  I don't see too much in the documentation.  I'd like to just cold store a little bitcoin on (3) USB sticks.  Are any of the following an ideal route:

(1)  Put Multibit client on all USB sticks, and copy ".wallet" file to all.
(2)  Put Multibit client on desktop, and just copy ".wallet" file to all USB sticks (i.e. ".wallet" file is really what I need to store)
(3)  Put Multibit client on desktop, and export ".key" file to all USB sticks

Thank you for any clarity.  I've installed the Multibit client on one USB stick, with the ".wallet" file there as well.  My guess is that I don't need to copy everything to the other two USB sticks for redundancy, and I suspect that might even mess something up or be overkill, particularly if the ".wallet" file changes after every time I send or receive bitcoins.  

Thanks for any help, for a partially technical n00b!  I understand Armory, or another wallet, may be "more secure", but unless their is some real significant advantage I just feel most comfortable with Multibit as I'm somewhat familiar with it already.

[jim618]

 I would go for an option very similiar to your (2).

a) Install MultiBit on your desktop, create a wallet (say it is called savings.wallet) and encrypt it.
b) Add however many receiving addresses you want for that wallet and label them.
c) Close MultiBit so that everything is written to disk.
d) You need to backup a minimum of the savings.wallet but I would go the extra mile and backup:
    d1) savings.wallet
    d2) savings.info
    d3) the directory savings-data and all its contents.
e) Copy the files in d) to your three separate USB drives.

As long as you don't create new receiving addresses for your wallet, your backups will still be valid.
I suggest saving the extra savings.info and savings-data because then you will also keep your label information (in the info file) together with the automatic backups of the wallet/ private keys (in the savings-data).

You will also need your password to use your wallet, so you would want to keep that safe somewhere.

If at some time in the future your desktop wallet was lost/ stolen you can then go to any of the backup USB drives and simply open the savings.wallet in MultiBit. When you open the wallet it automatically syncs with the blockchain to get all the transactions and work out the balance.

Note that if you create NEW receiving addresses you will have to update your backups, as you have created new private keys in your wallet.



 

[SheHadMANHands]

I would go for an option very similiar to your (2).

a) Install MultiBit on your desktop, create a wallet (say it is called savings.wallet) and encrypt it.
b) Add however many receiving addresses you want for that wallet and label them.
c) Close MultiBit so that everything is written to disk.
d) You need to backup a minimum of the savings.wallet but I would go the extra mile and backup:
    d1) savings.wallet
    d2) savings.info
    d3) the directory savings-data and all its contents.
e) Copy the files in d) to your three separate USB drives.

As long as you don't create new receiving addresses for your wallet, your backups will still be valid.
I suggest saving the extra savings.info and savings-data because then you will also keep your label information (in the info file) together with the automatic backups of the wallet/ private keys (in the savings-data).

You will also need your password to use your wallet, so you would want to keep that safe somewhere.

If at some time in the future your desktop wallet was lost/ stolen you can then go to any of the backup USB drives and simply open the savings.wallet in MultiBit. When you open the wallet it automatically syncs with the blockchain to get all the transactions and work out the balance.

Note that if you create NEW receiving addresses you will have to update your backups, as you have created new private keys in your wallet.



 

Great, thanks a lot.

Concerning the BOLDED, do you basically mean to secure the ".wallet" file with a good password?  Does this basically encrypt the file, or are you using a separate application for encryption.  If the latter, what is wrong with just securing the ".wallet" file with a good password that can't be brute forced easily?

I suggest saving the extra savings.info and savings-data because then you will also keep your label information (in the info file) together with the automatic backups of the wallet/ private keys (in the savings-data).

Ok.  I know there's also an option to export your private keys with a password lock.  It sounds like you're saying you don't need to manually do this (export a ".key" file), as it will be in the savings-data folder, which automatically backs your keys up (I assume with your wallet password)?

Thanks again for your help.

[jim618]

Yes by 'encrypt' I mean use the 'File | Add Password'.

This encrypts the private keys and also automatically does an export of the private keys to a '.key' file, encrypted with the wallet password.

[tclo]

I would add that you might as well encrypt the backups of wallet.dat file with PGP, TrueCrypt or similar.  That should just add an extra layer of security.

[jim618]

That is a good point tclo makes.

If you want to make your backups totally opaque you would want to encrypt the whole file.
With the private keys encrypted you can still see the transactions in the wallet (i.e. the addresses and the amounts you sent and received)

If you are using a cloud backup you'd want to do this to prevent anybody snooping on your wallet contents.

[ArpFlush]

I have a (test) wallet in Multibit and I copied all files (except the "log" folder) located in ..\AppData\Roaming\MultiBit to a Truecrypt container file. After that I deleted the original wallet files. I then opened Multibit, clicked "Open Wallet" (the one in the Truecrypt container) and it works like a charm