Lightning node + Zeus with Lightning terminal

[Bratislava]

I folks pretty new to lightning Im running my node and wanted to setup wallets for my family (off TOR or VPN) so I went with Zeus connected through Lightning terminal. For sending and receiving works pretty good but I was surprised when a transaction between 2 wallets of my family was routed through ACINQ and fees were charged.
As far I know in this setup the sats of the family members are sitting on my node until they are sent outside, I thought that transaction between the family members would be just some "accounting entry" on my node without sending out and in the sats through some other nodes.


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Central European node: Bratislava
03a858314a8b0bda32475cb90c34056d3a4faeb00a88489f4fd7689cc39b208c84
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[NotATether]

Technically you create many LN wallets by opening a corresponding number of channels to other nodes.

So when each family member has their own channel (it works best with one, highly reliable channel), then it's like they each have their own balance.

I don't think there is a concept of locality in the lightning network. All channels are connected on a grid, kinda like how the mainnet works - the nodes are not all connected to each other but they each have their own peers.

So when you send an LN payment between two family members it will almost always go through some other channels. Unless maybe, and I emphasize the word maybe here, all the channels you opened for them go to the same node, but even that does not guarantee it as channels could become unavailable or have unfavorable routing policies.

[_act_]

If you directly connect your own node with another of your family node, the bitcoin you send through that channel will not have any fee, buy if you send money to another person using another channel but the node runner of the channel set fee for it, you will be charged small amout of money which is usual. You sent money to another of your family through a channel that requires you to pay fee. But the fee is very low and nothing to be bothered about.

[Bratislava]

If you directly connect your own node with another of your family node, the bitcoin you send through that channel will not have any fee, buy if you send money to another person using another channel but the node runner of the channel set fee for it, you will be charged small amout of money which is usual. You sent money to another of your family through a channel that requires you to pay fee. But the fee is very low and nothing to be bothered about.

I have one node and this node has multiple wallets for family members.

[nc50lc]

I have one node and this node has multiple wallets for family members.

How about channels?
Does each of your family members has separate channels connected to different lightning nodes?

As far I know in this setup the sats of the family members are sitting on my node until they are sent outside, I thought that transaction between the family members would be just some "accounting entry" on my node without sending out and in the sats through some other nodes.

It's the channels that hodls the bitcoins, not the lightning node.
The lightning wallet just shows the accumulated capacity if the channels it manage but it's actually broken down per channel.
Sending requires the node to calculate an optimum route from your channel to your brother's channel.

So my guess without any info about your setup: it may have found that routing it through the channel connected to ACINQ's node is cheaper than Bratislava.
Or there's an option that disables routing through your node so it used other channel's node to route.

[Bratislava]

There is 1 node with multiple wallets. Each family member uses the same node. I opened the "lightning terminal" then navigated to Connect => Lightning node connect, created a new connection choose "custodial account" and scanned the QR with ZEUS wallet.
the node, channels, liquidity is same for everybody.

I have one node and this node has multiple wallets for family members.

How about channels?
Does each of your family members has separate channels connected to different lightning nodes?

As far I know in this setup the sats of the family members are sitting on my node until they are sent outside, I thought that transaction between the family members would be just some "accounting entry" on my node without sending out and in the sats through some other nodes.

It's the channels that hodls the bitcoins, not the lightning node.
The lightning wallet just shows the accumulated capacity if the channels it manage but it's actually broken down per channel.
Sending requires the node to calculate an optimum route from your channel to your brother's channel.

So my guess without any info about your setup: it may have found that routing it through the channel connected to ACINQ's node is cheaper than Bratislava.
Or there's an option that disables routing through your node so it used other channel's node to route.

[nc50lc]

There is 1 node with multiple wallets. Each family member uses the same node. I opened the "lightning terminal" then navigated to Connect => Lightning node connect, created a new connection choose "custodial account" and scanned the QR with ZEUS wallet.
the node, channels, liquidity is same for everybody.

How about channels?
Does each of your family members has separate channels connected to different lightning nodes?

Okay, so the statement in the OP now checks out; it's a "custodial account" setup where your node is the custodian.
AFAIK, each custodial account should have a "virtual balance" that's managed by your lightning node rather than actual channel capacity.
Unfortunately, now that it's clear, I came up with the same question why it was routed.

Is this consistent to other transactions between your custodial accounts?
If not, investigate the wallets where it occurred, both sender and receiver.