LoyceV's 0.1 sat/vbyte Electrum Server Adventure

[LoyceV]

I've added the only clearnet node from @Pmalek post (I'd feel better if the list would be bigger).

I didn't add this, and it still worked

A small suggestion would be to maybe centralize all this into the first post so the ones even lazier than me (who also have local ElectrumX) can use it.

It was more meant to be my own personal log, it's too experimental to be a complete guide.

[NeuroticFish]

I've added the only clearnet node from @Pmalek post (I'd feel better if the list would be bigger).

I didn't add this, and it still worked

It's not unexpected, especially given to the fact that it literally took one second from my (second) low-fee tx being broadcasted from Electrum to be visible on mempool.space
But a few more hardcoded relay nodes... give a nice peace of mind this early in the low-fee "era".

all[/i] suggestion would be to maybe centralize all this into the first post so the ones even lazier than me (who also have local ElectrumX) can use it.

It was more meant to be my own personal log, it's too experimental to be a complete guide.

LOL, no! My confirmation was supposed to tell it already works pretty much out-of-the box (of course, if you already have bitcoind and fulcrum already in place and a new enough Electrum).
Of course, it's your topic. I am already happy with what I've got.

[Cricktor]

I forgot and can't figure out anymore where I found last Saturday this source of presumably sub 1sat/vB peers which should've minfeefilter < 1sat/vB (shown when you query bitcoin-cli getpeerinfo for details of your Core's peers):
https://gist.github.com/ottosch/1aa7ef9a8a3971c19ef8a148931d4f49
(I must have used private browser window as there's no helpful browsing history when I tried to see what site I browsed before I hit above link. I couldn't find above link with ninjastic.space here in this forum either. Apologies if I screwed up a source within this forum.)

I tried a few of the onion peers but not all are in the ballpark of 0.1sat/vB for lower limit. Some were only little below 1sat/vB, so I had to remove those connections from my node.

I didn't check any of the clearnet nodes. Anyway, I hope it still helps a little bit.

[joker_josue]

Server is running: electrum.loyce.club:50002
I still need to change the minimum relay fee. Done.
I still need a better domain name.

I'm surprised to see 190 clients connected already, just minutes after I created the SSL certificate.

You set up a node/server and you didn't say anythin.

It was an excellent idea. I had thought about it, but I ended up not (yet) moving forward.
Very nice and thank you. It will help the community.

I'll carefully analyze your steps when you build one too.
Then can I bother asking for help?

The main question is: is it working well and being able to make low-fee transactions?

[LoyceV]

You set up a node/server and you didn't say anythin.

Lol. I opened a topic didn't I

I'll carefully analyze your steps when you build one too.
Then can I bother asking for help?

Everything I know is in the OP already

The main question is: is it working well and being able to make low-fee transactions?

It worked for me. Try it

[joker_josue]

The main question is: is it working well and being able to make low-fee transactions?

It worked for me. Try it

I'll do it! At least we know you're more confident than many other public servants. 

How long did it take to synchronize the entire blockchain?

I've been looking around and I'm finding a VPS with 1TB of storage at a reasonably good price. 
I'll look into it a bit more, or maybe step it up a notch and build my own server... under consideration...

[LoyceV]

How long did it take to synchronize the entire blockchain?

I think almost 2 days for Bitcoin Core, and even longer for Fulcrum. But I think having blocks on network storage is what slowed it down a lot.

I've been looking around and I'm finding a VPS with 1TB of storage at a reasonably good price.  

1 TB is going to be tight for Bitcoin Core and Fulcrum. It may still fit, but won't fit for long.

I use servaRICA's Black Friday offer. I have this:

Code:

8x: Unified Slim Plan 1 Slice	4GB	1	125GB NVMe

Plus 2 TB SAN Storage Expansion. It's supposed to have dedicated CPU cores, but I sometimes see CPU steal up to 60%. Each core is quite a lot slower than my dedicated Xeon used to be, and that wasn't a very recent system, so I suspect I may be getting half cores. But for the price ($220/year), it's okay. Although it was turned off for no apparent reason a month ago, and I had to manually turn it on again. That was weird, support didn't tell me a reason.

I want to upgrade to this offer, but they've been out of stock for a while:

Code:

4x FAT Slice 2	2 Dedicated Cores	8GB	500GB

Or maybe 6x And some SAN storage. That way I'll have more NVMe storage. This should be in stock again next month.

[joker_josue]

I've been looking around and I'm finding a VPS with 1TB of storage at a reasonably good price.  

1 TB is going to be tight for Bitcoin Core and Fulcrum. It may still fit, but won't fit for long.

I actually want something like 2TB.

I happened to be testing BTCPay Server using the Netcup VPS 500 G11s, with the blockchain being pruned. Maybe I can see if I can add more space.

But I get your point: a "lower" service and then additional space.
See if that's a big initial investment. See if I can find any promos on this "forum".

[LoyceV]

I happened to be testing BTCPay Server using the Netcup VPS 500 G11s, with the blockchain being pruned.

Only 4 GB RAM can't be fun with Bitcoin Core.

But I get your point: a "lower" service and then additional space.

If it wasn't clear: Servarica adds "slices", so 8x means 8 times more CPU, RAM and storage.

See if I can find any promos on this "forum".

I've seen good and bad hosts on Lowendtalk, and I've seen good hosts turn bad. But as long as it's not a critical application, I don't need very expensive redundant cloud storage and prefer a much lower annual hosting fee. I'm already looking forward to new Black Friday offers from some hosts.

[joker_josue]

See if I can find any promos on this "forum".

I've seen good and bad hosts on Lowendtalk, and I've seen good hosts turn bad. But as long as it's not a critical application, I don't need very expensive redundant cloud storage and prefer a much lower annual hosting fee. I'm already looking forward to new Black Friday offers from some hosts.

I'm thinking of switching to VPS 1000 G11 or VPS 2000 G11 which will be better for this operation.

Netcup is the best value I've found. I'm looking for more consistent service because I don't want to keep jumping from one service to another and want something that lasts longer.

Maybe wait until Black Friday to see if they have any interesting promotions.

[LoyceV]

I was looking at Fulcrum's "getinfo" command. Some interesting parts:

Code:

    "clients_connected": 248,
    "clients_connected_max_lifetime": 334,
    "clients_connected_total_lifetime": 403638,

    "mempool": {
        "addresses": 8459,
        "avg_fee_sats_B": 0.09,
        "avg_fee_sats_vB": 0.2,
        "size_bytes": 66121778,
        "size_vbytes": 29260364,
        "txs": 92805

    "txs_sent": 150,
    "txs_sent_bytes": 100307,
    "uptime": "9.34 days",
    "utxoset": {
        "size": 168028344,
        "size_MB": 14114.38

So 150 transactions were broadcasted through my server. Only one of them was mine. At least this confirms there was a need for this
I like the average fee, but keep in mind this is the average in mempool, not in confirmed transactions.

I set a donation address in Fulcrum's settings, but Electrum > Help > Donate to server shows: "No donation address for this server". I checked other Electrum servers, and they all show the same error message. That used to work a few years ago, but it looks like Electrum no longer shows the server's addy. If anyone knows how to fix this, feel free to post.

[joker_josue]

So 150 transactions were broadcasted through my server. Only one of them was mine. At least this confirms there was a need for this
I like the average fee, but keep in mind this is the average in mempool, not in confirmed transactions.

What we need is more reliable servers.
I hope to soon help with this and be able to set up a public server that guarantees privacy, so that everyone can use it. 



@LoyceV is your Electrum currently only connected to your server, or do you maintain others? I also ask who is using LoyceV server.

[LoyceV]

@LoyceV is your Electrum currently only connected to your server, or do you maintain others?

I manually set Electrum to only connect to my server. That makes it faster for me to detect if my Fulcrum server stops running for some reason.

I also ask who is using LoyceV server.

Don't tell me those things, I don't need to know!

[joker_josue]

I also ask who is using LoyceV server.

Don't tell me those things, I don't need to know!

You are right!
But, if you don't log in either, it's irrelevant to know.

By the way, is the server in Europe or another country?

In Electrum, is it possible to choose more than one manually, or just one?

[LoyceV]

By the way, is the server in Europe or another country?

It's in Montreal, Canada.

In Electrum, is it possible to choose more than one manually, or just one?

Manual server selection shows it's connected to 10 nodes.
Connect only to a single server connects to just one. That way you won't notice if the server is lagging blocks. I use "Manual".

[Cricktor]

In Electrum, is it possible to choose more than one manually, or just one?

That's an interesting question. I operate my personal (yet non-public Fulcrum!) Electrum server for the purpose of enhanced privacy. My SPV wallets only have to talk to my own Fulcrum server, no wallet's address details are "leaked" to other Electrum servers.

E.g. I invoke my Electrum wallet with the following command line options:

Code:

--oneserver --server umbrel:50002:t

The --oneserver tells my Electrum wallet to talk only to the Electrum server that's specified in the --server ... part. No other Electrum servers are discovered or contacted.

I would assume, but haven't checked myself yet, that you could specify multiple --server ... addresses to which your Electrum connects. But this needs confirmation by someone who has already tried this with success.

[nc50lc]

I would assume, but haven't checked myself yet, that you could specify multiple --server ... addresses to which your Electrum connects. But this needs confirmation by someone who has already tried this with success.

Electrum will start without error since the arg is valid.
But it will only accept the last --server arg because although all were parsed, the first --server arg is overwritten by the next, and so on.

e.g. (command):

Code:

$ python run_electrum --server electrum.blockstream.info:50002:s --server electrum.jochen-hoenicke.de:50006:s --server electrum.labrie.ca:50002:s

e.g.: (logs):

Code:

20250903T044621.243479Z |     INFO | network | starting network
20250903T044621.243479Z |     INFO | network | connecting to electrum.labrie.ca:50002:s as new interface
.
.
20250903T044627.993570Z |     INFO | interface.[electrum.labrie.ca:50002] | set blockchain with height 912964
20250903T044627.993570Z |     INFO | interface.[electrum.labrie.ca:50002] | new chain tip. height=912965
.
.
20250903T044628.024734Z |     INFO | interface.[electrum.hodlister.co:50002] | connection established. version: ['ElectrumX 1.10.0', '1.4']
20250903T044628.024734Z |     INFO | interface.[btc.electroncash.dk:60002] | connection established. version: ['Fulcrum 1.12.0', '1.4']
20250903T044628.024734Z |     INFO | interface.[paris.anties.org:50002] | connection established. version: ['ElectrumX 1.16.0', '1.4']

Picked the last --server arg but the others are still random. Switching the last --server will make it the manually selected server.

Same thing happens if I forced to edit the "config" file to have more than one "server":"<server>", line.
Only the last one was accepted and the rest were deleted after the config auto-update itself.

But for clarification, those "other servers" aren't used like the selected server.
Those are mainly used for fork detection (and fee rate), your client will only request for "block_headers" so they will not know your bitcoin addresses.

[joker_josue]

But, in short, is it possible for me to choose 3 or 4 different servers, to all be connected to Electrum?

Because, from what I understand, it is only possible to choose one, or leave it automatic and Electrum randomly chooses the maximum 10 servers.

[nc50lc]

But, in short, is it possible for me to choose 3 or 4 different servers, to all be connected to Electrum?

No, just one, let's say "main server" of your choice.
The rest (peers) are just for security purposes since you can't just trust that a random public server is giving you accurate information.
And those don't have access to your wallet's addresses so it's not bad to keep it randomized.

[LoyceV]

But, in short, is it possible for me to choose 3 or 4 different servers, to all be connected to Electrum?

I don't think that's possible. I'm okay with "Manual server selection": it only connects to my own server, but when my server has a problem, Electrum tells me it's lagging or offline. So if you want to use a few selected servers, I'd say pick one, and switch when there's a problem.