Bitcoin Forum

Hi everyone

What is the cold storage wallet?

And how to do that?

Thanks in advance.

A wallet is considered cold if it is kept offline without any internet connection. In order to broadcast transactions and keep up to date on your balances you also need a watch only wallet that is online, but does not have the private keys in order to sign a transaction. The watch only wallet creates the transaction, but cant sign it. You transfer it to the offline computer (e.g. via QR-code or USB-stick), sign it there and transfer it back for broadcasting.


#1 get additional computer
#2 install software
#3 dont go online

A properly done paper wallet is hard to beat.  You have to treat it safely and do it at home.

Also store it in a safe area. And make a backup do not just have one copy.  But if done properly a paper wallet an be hard to beat.

For more clear info: https://en.bitcoin.it/wiki/Cold_storage

Use paper wallet is cheap and of course secure.

most likely a hardware wallet is save enough too:

https://bitcointalk.org/index.php?topic=899253.0

Cold storage wallets are wallets that aren't connected to the internet to prevent being compromised. Cold storage wallets usually contain a large amount of bitcoins and is purposely done so as to prevent someone from spending it and only keeping it for long-term. It comes in several forms, though the most widely-used form is the paper wallet which could be printed and be kept somewhere safe. Hardware wallets are also a thing, and it is also a cool and secure way to keep your bitcoins. Suggestion for a hardware wallet: Trezor.

So that's a cold wallet means.

I always read that term together with hot wallet in multiple sections of this forum.

Thanks OP for asking this and for those posters who replied and give information for us new.

in my case i prefer to have multiple cold storage wallet, so in the event that i need to connect one usb containing the wallet, and thus it became a hot wallet, and in the same time my pc is infected by an obscured wallet stealer, i'll not lose many coins

I'll try to explain simply

Cold storage wallet is a wallet that you are not going to use in many times and unless you need it

Hot wallet is the wallet you daily use for your transactions


you can create a cold wallet as simply as creating a paperwallet

A cold wallet is basically a wallet that you store offline, so on a usb-stick, hard disk.
By cold wallet it means that no one else but you can access it, so it can't be hacked.

any wallet that is created on an offline computer (or any other way that does not require a computer) and is kept offline can be called a cold storage.
it is for keeping your bitcoin safe from malware and theft.
depending on what kind of cold storage you want to use, making one can be different. easiest in my opinion is using an always offline computer and generate a wallet with Electrum.
there are step by step tutorials of creating cold storage (different ones) on the internet if you search.

i liked this thread for all the information it has in one place:
https://bitcointalk.org/index.php?topic=858604.0



but it is not free ;)

So what if the flash drive gone or got corrupted and you don't store any copy of backup in other drive? Does it retrievable?

Cold wallet is not "storing in a USB". Cold wallets means storing Bitcoins in a wallet which is not accessible connected to Internet(completely offline).

No. It is not retrievable but sometimes, you might be able to recover files from your USB stick. I highly recommend you to either create a second(digital) backup or print private keys.

PC > Offline Wallet (a file) > Flash Drive / Hard Drive > Is this how it goes? So it have a file extension? Damn sorry I have many questions. :(

What goes?

Three ways are:

 • Storing private keys in a completely offline hard disk and/or USB.
 • Printing or writing down private keys.
 • Memorize private key(s).

I mean what's those private keys look like when stored in offline hard disk or USB's? Like a file ? So it have file extensions?

Simple copying that "file" to other drive/usb can not became a backup? Or backup must do manually to other drive?

Thanks for the answer.

When you export the private key, the file is usually looks like "wallet.dat"


Just copying and save the file carefully, and you can import it, https://en.bitcoin.it/wiki/How_to_import_private_keys (actually it's easy step, just go to the wallet, find an import button and choose the file).

CMIIW.

if i have a paper wallet, how can i re-use it online?  ??? ::) or what is a paper wallet??

You can put it in a wallet to use online.   Normally it would be on a paper with private key/qr code.  And yes it can be re-used.  But I would spread money out not just in one.


Here is a example - https://blockchain.info/wallet/paper-tutorial

Thank you very much, i understood it now :D
Great link.. cheers.

Not a problem best of luck with it.  If you do one print it at home and on none networked printer if possible.

After make copies and make sure to keep them safe.

What if our printed paper is lost..?
We will loose all the coins? in it

If lost and you have no backup it is gone.   You will not have access to it.  This means don't loose them.

Store multiple in safe locations do not have just one.

 cold storage wallet keeps all the private-key data on the offline computer, only someone with physical access to the offline computer can can have access to the BTC stored in it.
in general cold storage wallet are offline wallets.


Methods of cold storage include keeping bitcoins:

#1 On a USB drive or other data storage medium in a safe place (e.g. safe deposit box, safe)
#2 On a paper wallet
#3 On a bearer item such as a physical bitcoin.
#4 Online, but on encrypted media where the encryption key is offline.
#5 Use a offline Bitcoin Hardware wallet

Basically i understood that Cold Storage Wallet is saving your coins offline, and can be used later on.
We can save it in different mediums.

Right? :)

that is correct.
as long as you made the wallet (private keys) offline and away from any malware with legit software, it can be considered cold storage.
i personally like offline linux on my USB

How can a malwareaffect my cold storge lol?

If done right no it can't.  That's the whole point of being offline.  You are not online for malware to get it.

If done wrong, or computer was compromised before making yes you could have issues with malware.

Please can you explain something more>

basically if while you are storing your wallet, the pc is infected, it could infect your usb too, so it will not be safe, next time you will connect it a bad surprise might happen

it is advisable to do a cold wallet in a 100% secure pc, to be sure that you're not infected, you need a secure erase first then, you run the client BEFORE everything else

another trick(i'm actually using this, i find it pretty convenient to fight infection) is to have a small amount in your main desktop, on which you connect your usb, if that small amount is still there, you know at 100% that your pc is safe

I agree with paper wallets for OP. Current best option and cheapest.

That's I want to know. So .dat is the file extension. Thanks for the info Sir.

No. There is no certain extension for files with private keys. Wallet.dat contains a few other things other than private keys and you will need a wallet which is compatible with that wallet.dat. Therefore, it is better to save private keys in a text file. If you want, encrypt it.

Main wallet is the core wallet that uses wallet.dat .   It's not a bad thing to have on a thumb drive to save.  But defintally keep the private key's.

I personally really like paper wallet's.  They are a great way to store key's offline and in safe places.   They are cold and no online in anyway.

Malware can infect the computer and have the potential to reduce the randomness when generating the private key (I don't know any malware that can do that however). Even if it is offline, the malware can send the private key once its online.

For the linux part, its pretty much just about preferences. If you're offline, you would be safe regardless of what OS you use as long as the RNG is random.
Thumbdrives are usually quite fragile and hardware failures can occur. You can easily laminate the private key and it would be quite safe from water and probably wouldn't fade for a long tim.

A "cold" storage wallet, for me at least, is like a savings account at the bank. I don't access it often and it holds most of my bitcoins. It should also be very safely kept for this reason.

Cold storage is where a person stores their Bitcoin holdings offline. I don't know what the best method is for putting Bitcoins in cold storage, but there are many different methods.

A cold storage is a storage under -0 degres. ;D ;D
Sorry I could not resist.  ;D  

But speaking seriously a cold storage(usb for example) help you to keep a backup of your wallet on a safe place.

Basically you write/print the sensitive data to a piece of paper.

You can use it online by either entering the private key manually into an online wallet like blockchain.info.

You can import private key from anywhere and that private key must be kept very securely, physically.

without going too much in the trouble zone and complicated thing, i would advice for newbie to buy a new hdd or sdd, or do a format/secure erase, and install core before everything, then you have a 100% secure machine on which you can do any cold storage

no need to go to fancy website removing connection or anything like that

in addition i would suggest doing everything in linux if you are familiar with its environment.

windows has a lot of exploits and malwares which does not exist in linux.

well this is debatable, the last security hole was discovered in linux, i'm not so sure if recently linux is still so superior in the "virus" departments" versus windows, especially with the new windows 10 that help even more against seccurity

i used linux but i can't stand the whole typing thing in the console, it's seems only a way to make thing more long to do, and i prefer to use the mouse to be honest, much faster, but to each their own i guess...

interesting information on that security hole, but from what i have read (the news is for 2015) but the issue seems to be an old one and was fixed in 2013 !

i also found some interesting information on open source vs closed source systems:
http://security.stackexchange.com/questions/4441/open-source-vs-closed-source-systems

and i think in linux you can do everything with mouse like in windows too.

yeah this is true, but at that point, i prefer to use windows, more comfortable, linux was born with console, and anyway i never lost any coin with windows, so what is matter is the PEBCAK ;)

also gaming in linux is severely limited

p.s. i don't know if we are talking about the same security problem, but i'm not referring to the "Ghost" problem