Completely airgapped blockchain setup

I'm looking to use a laptop that’s never online to sign transactions, but I’m not a fan of how it shows 0 BTC. I know about using a node with a watch-only wallet, but I want to see the BTC balance directly on the airgapped laptop too. So, I figured, I've already got the full blockchain on my connected laptop, so why not copy the blockchain files over to the airgapped one every week or so using something secure like optical media? This way, I’d have two backups of the blockchain and I could also see the BTC value on the offline laptop, which would make me feel better. I want everything organized with the right dates and all, unlike the watch-only wallet where I had to manually label transactions. So, here’s my question: is this a viable approach, and can I still use PSBT as usual? I’ve seen others doing it without issues. The only real risk would be using media that might carry malware for transferring the blockchain files, but that seems pretty unlikely if I’m careful. I also update my offline Linux laptop sometimes using offline methods, so it’s the same cautious strategy. Plus, I can boot from Tails to transfer the files so I won’t be using any compromised OS. I’m aware of the risks, but I think they’re pretty minimal. Honestly, you have a higher chance of getting robbed if you use a hardware wallet since the company has your info and you’re known as a wallet owner. Just looking for any technical feedback.

It sounds like you're going to compromise security for aesthetics. One way or another, this always adds risks, so I wouldn't do it.

The main advantage of an air-gapped device is that it reduces your interaction with online environments. you ONLY need raw data signature form the other device, but currently, you need two laptops and additional storage space for both, which is more than the cost of buying a new Hardware wallet. I think you forgot that you asked this question before.

Copying the full blockchain to an air-gapped device is actually not solving any problem in this set up, it will just add unnecessary complexity. He is going to compromise security for convenience of seeing BTC balance. A watch-only wallet can handle that need. The main principle of air-gap device is to minimize data transfer. Copying data weekly goes against this principle. To me, copying the entire blockchain regularly just to view balance is inefficient. It is like downloading the whole library just to check one page of a book.

You asked google answered   So the growth rate is around 0.2–0.3 GB per day. At that pace  1 TB SSD will become obsolete fairly soon  especially since you need to reserve about 20% of its capacity for overprovisioning to maintain good performance. My node runs on  2 TB SSD, and I keep the second 1 TB SSD as  backup.

Can't believe 1 TB SSD won't be enough soon. It's such a bad time since pricing is rising too. Well, I guess most people have some spare storage/SSDs if they're serious about running a node. Anyway, I agree with others. If your issue is just not being able to see your balance, there are other solutions that won't compromise security. Alternatively, accept it as the trade-off.

I think as time goes on some people might actually decides to stick to running of prune node instead of the full node just to save cost of buying disks for larger space. No matter how anybody puts it out there as long as there is an iota of doubt of the device been infected with malware, it stops been an airgapped device for me. The question OP asks is a bit off to me because how he not want to see his balance on a watch only wallet when he definitely must still use the wallet for creating and broadcasting of the transaction

I accept the risks involved, which I think are minimal, and you have way better odds at ending up robbed if you use a hardware wallet as a company has now your dox plus you being an owner of a hardware wallet. The 2 laptop setup is way safer. Im just asking if there are any technical problems doing this. I assume it's exactly the same, you just have the convenience of seeing what is actually going on on your offline laptop without trusting the online node code is making it show things accurately. Watch-only wallets are also annoying as I described because they do not have labels and transactions are not properly shown in order: https://bitcointalk.org/index.php?topic=5576086.0 So please, do not lecture me in the risks of moving data into your offline laptop. I understand it, I just feel safer, psychologically even, if I see the actual BTC count, and the transactions properly labeled and in correct time order. When im making transactions im already moving data with the PSBT files anyway, and I rarely make transactions, so the window of opportunity of any attacks is near zero. There are way bigger chances that your Trezor phones home, or your Ledger purchase leaks in a data breach on their company and now you are at risk of 5$ wrench attacks etc. I would never use a hardware wallet because of that. On the other hand, here im dealing with open source code, with hardware I control that is not attached to a dox that says "you own a hardware wallet", and there is a near zero attack surface since any data is being moved offline, when rarely moved, with a layer of protection (two computers offline using Tails) or even optical media through fully encrypted devices. The peace of mind I would get from seeing that the funds are indeed there, are worth it for me, plus getting all the transactions in order, with all labels etc, without having to fully trust that the online node is showing things properly, and like I said, I barely make transactions these days, so I could just update the blockchain every x months when I want to make a transaction. I simply do not want to trust the PSBT thing is working as intended. All this descriptors stuff, there is so much new stuff on BTC compared to many years ago, I don't have the time to keep track of everything. I want to see my funds visible "as-is". Then I can work from there. Remember that sometimes software mistakes happen. Like we just saw some bug that deleted wallets during migration. The less things I have to trust the best. So I want the funds shown on the same device, with the full blockchain, and I can then make transactions from a place where I feel confident everything is ok, and not be paranoid about missing change addresses, using the wrong address because it's not labeled properly or in the wrong chronological order etc. The only conclusion I have found is that this is the best thing to do. Specially if you have an old wallet from 10+years. It's crazy, this ordinals crap is really going to cripple the network as people start dropping nodes.

There aren't any, you can definitely do this and I have done this in the past (but not in an airgap setup). Just make sure that you use very reliable media with good cables, or otherwise you will frequently run into resyncing issues. I've had those nightmares in the past, and that definitely becomes a time sink for things that should be very fast and easy to do. External SSD should work. If you were to use actual computers even in a mini factor, I would recommend connecting to SATA each time instead. It has nothing to do with ordinals. That does not even represent a tiny percentage of the total storage. Bitcoin's blockchain will become big due to the time-factor. It is already extremely limited at 4 MB's for the year 2026. If a user can't afford a 1TB SSDs, they do not have enough money to use Bitcoin anyway or they are completely mismanaging their finances. Don't make me bring up data about subscription services. Anyway, right now almost nobody uses Ordinals, Runes or any of that crap.

As in DVD or bluray? It's more realistic to mount external HDD/SSD on read-only mode while also disallow executable running from it. Not exactly technical problem, but you should pay attention which file you copy. You don't want to copy setting from different device by accident.

Question: what makes you call optical media safe? Is that because you can't write back to the media from your offline system, or are you assuming you can't get malware on optical media? If not for you, a warning is still in place for others who read your topic later. I highly doubt that, considering the basic questions you're asking like:

Why not just use a seed signer device? If all you want is the aesthetics of reading the "BTC" number on your screen, while enjoying the security of an airgapped environment, then just take your laptop, put some linux, download Bitcoin Core, let it sync, download Sparrow and set up a wallet via your SeedSigner. Manually copying the blockchain from an internet connected computer to your airgapped laptop might also work, but just why...

i can see running a totally offline fairly current blockchain purely on an airgapped computer. just copy the blockchain folders from a current internet connected node over via what, HD/tape/carrier pigeon/whatever every week or so, and run core on the airgapped rig and then you can bounce any addys you want off of it for fun/profit with your vibe coded softwarez on the airgapped system as for why? lol because compute is cheap lately with all the systems that arent rated for win11 being dumped. tinypcs rock.

Bitcoiners won so much that they're now vibe coding on airgapped systems and calling it entertainment.

Seeing this level of paranoia and asking to not be lectured about the risks of moving data to an Airgapped Computer because you feel mentally better knowing you can see the Bitcoin number on your screen is insane. You mentioned you are already using Tails.  What stops you from starting a Tails session and importing your used Addresses in to a temporary Electrum only when you want to check how much Bitcoin you have and the correct time stamps?  It sounds much more Secure than putting some new data in the computer you are supposed to have separated from the external world..

I don't want to add additional complexity by using other software, let alone other hardware. To answer some previous basic questions such as "why use optical media". It's safer because you cannot add some script there as you could with an USB, it's also write only. In any case, you can plug your drive which you only use for the online node on your offline laptop and copy the block files there using Tails so no realistic surface attack is possible in case you don't want to deal with dvds. This tradeoff is worth it. You get actual existing funds, with correct labels and correct time order, which you cannot have in watch-only wallets because when you import the descriptors it doesn't know how to properly order them (they are all dumped with the same date if the "timestamp" value is the same) for instance.

You are already complicating things yourself by wanting to see bitcoin address update on airgapped device. Yeah but optical media are getting less support and they are not being used for some time, so I wouldn't be surprised if operating systems starts phasing out support slowly. I removed CD drive from my laptop long time ago, and recently I wanted to burn one disc for one old car audio player, so I returned drive temporary. To short my story I was unable to burn disc in my Fedora linux because of some stupid error, and I installed all possible software. I also found one of my old disc with some movies, and it would not load in any operating system, it basically got broken from collecting dust, proving how fragile and easily scratched compact discs are.

The OS doesn't matter, but a different drive might still get it to work.

Nope. I tried several other discs and they are working fine, only one with movies is not working. And I keep them all in exactly the same way, they are protected from scratches in separate purse with separators. I almost forgot how loud those cd/dvd drives are, loading every time computer boots up