I’d like to setup an automated process to email my encrypted wallet to myself, so that if, for instance, my house burns down, I’ve got easy access to a recent copy of my wallet stored off-site.
I’ve seen this mentioned in a couple places as a method for backing up a wallet, but none of the more thorough security guides I’ve read mention this as either a good or bad thing to do.
So, is this a stupidly insecure thing to do, or a reasonable means of keeping a regular automated off-site backup of a wallet?
The wallet.dat contains not just encryption keys but addresses as well. If you are using the encrypt feature from the Bitcoin client to encrypted the keys then mailed to yourself those keys in the wallet would be secure assuming you used a strong passphrase and that passphrase is not used elsewhere.
But the transactions in that wallet can be viewed by anyone with access to the backup file.