Can You Identify the Node Used for a Past Transaction?

Been using Electrum for ages, can't even recall when I started. I've been pondering the whole fee/dust limit thing lately and I wonder... is there any way to find out which node I used to broadcast a specific transaction?

Check out this thread from a while back about testing some dust transactions for segwit and non-segwit addresses. You could try connecting to different nodes with known min relay fees, see if they even accept dust transactions. If you're on Electrum, servers like LoyceV's and DireWolfM14's might help you.

I got a tiny 40 sat transaction last year. That's where I started digging.

I hear you, but what I'm really asking is if I can look back at a transaction from a few weeks ago and find out which node sent it out into the wild. I've done some digging, but it seems impossible... still looking for loopholes.

Not happening. When you connect to a node, that’s the first one to grab your transaction. From there, it spreads to other nodes until it gets mined. Sure, you can see which mining pool mined your transaction, but the nodes? Nope. Can’t track that.

Looked through the Electrum code, found nothing that logs those details. You might be able to tweak the code to save a local log for future transactions, but that won't help with past ones. If you had a specific server, you’d have a shot, but sounds like you don't.

Like mcdouglasx said, it's not possible. You can enable logs to see which Electrum server you were using, but that’s about it. Then you’d have to match up the timestamp of your transaction with the log. It could get tricky if the transaction was signed and saved locally but sent later.

But hey, what could stop OP from just picking a node to broadcast their transaction now? Seems like a solid plan.

You kinda missed it. OP’s asking about past transactions. If they didn’t have a fixed Electrum server back then, it’s a lost cause.

I didn’t miss it. OP is looking to prepare for the future. If they wanna track nodes in the future, they just need to apply that method consistently. Only thing is, I don’t see the point of doing it.

I searched around but found nothing. Google didn't pull up anything useful on OP's question either. Even ChatGPT wasn’t any help.

Curious why you care about where your past transactions were broadcasted? Just wondering.

Lol why so curious about my curiosity? I made a broadcast a few weeks ago and I think I used around 0.5 sats/vbyte but I forgot which node I was on. Just curious, really. Kinda funny how I need desktop Electrum for this stuff; mobile's lacking in features.

I don’t know many Electrum servers that accept transactions under 1 sat/vbyte. There's LoyceV and another one I tried, but it’s been offline. Man, Electrum desktop is way better than mobile. If you’re on Android, try Blue Wallet.

Are you just looking to send below 1 sat/vbyte? A few months back, I was fine with 0.2 sat/vbyte, but I run my own private server. But honestly, with the mempool this full, you’re asking for trouble. I sent BTC with 1.56 sat/vbyte and it took ages to confirm.

No way it’s good this could happen. If it did, it'd leak privacy like crazy. Imagine how easy it’d be for snoops to track stuff. I remember blockchain.info used to log IPs of the last node that relayed transactions but that was ages ago.

Logging IPs isn’t useful either. Just because it’s noted doesn’t mean it’s the originating node. If you connect directly to one node, all transactions go through it initially, which can mislead the logs.

Right? Sending sub 1 sat/vbyte transactions right now isn’t smart. Just looked at the mempool and you’d need at least 1.2 sat/vbyte for any chance of a quick confirmation. At 0.2 sat/vbyte, there’s a ton of unconfirmed transactions piling up.