Attempts loop out the target amount into either the backing lnd's
Attempts to loop out the target amount into either the backing lnd's
wallet, or a targeted address.
The amount is to be specified in satoshis.
@ -158,9 +158,12 @@ DESCRIPTION:
specified. If not specified, a new wallet address will be generated.
OPTIONS:
--channel value the 8-byte compact channel ID of the channel to loop out (default: 0)
--addr value the optional address that the looped out funds should be sent to, if left blank the funds will go to lnd's wallet
--amt value the amount in satoshis to loop out (default: 0)
--channel value the 8-byte compact channel ID of the channel to loop out (default: 0)
--addr value the optional address that the looped out funds should be sent to, if let blank the funds will go to lnd's wallet
--amt value the amount in satoshis to loop out (default: 0)
--conf_target value the number of blocks from the swap initiation height that the on-chain HTLC should be swept within (default: 6)
--max_swap_routing_fee value the max off-chain swap routing fee in satoshis, if not specified, a default max fee will be used (default: 0)
--fast Indicate you want to swap immediately, paying potentially a higher fee. If not set the swap server might choose to wait up to 30 minutes before publishing the swap HTLC on-chain, to save on its chain fees. Not setting this flag therefore might result in a lower swap fee.
```
It's possible to receive more inbound capacity on a particular channel
@ -178,6 +181,79 @@ swap is initiated successfully, `loopd` will see the process through.
To query in-flight swap statuses, run `loop monitor`.
### Fees explained
The following is an example output of a 0.01 BTC fast (non-batched) Loop Out
swap from `testnet`:
```bash
$ loop out --amt 1000000 --fast
Max swap fees for 1000000 sat Loop Out: 36046 sat
Fast swap requested.
CONTINUE SWAP? (y/n), expand fee detail (x): x
Estimated on-chain sweep fee: 149 sat
Max on-chain sweep fee: 14900 sat
Max off-chain swap routing fee: 20010 sat
Max off-chain prepay routing fee: 36 sat
Max no show penalty (prepay): 1337 sat
Max swap fee: 1100 sat
CONTINUE SWAP? (y/n):
```
Explanation:
- **Max swap fees for <x> sat Loop Out** (36046 sat): The absolute maximum in
fees that need to be paid. This includes on-chain and off-chain fees. This
represents the ceiling or worst-case scenario. The actual fees will likely be
lower. This is the sum of `14900 + 20010 + 36 + 1100` (see below).
- **Estimated on-chain sweep fee** (149 sat): The estimated cost to sweep the
HTLC in case of success, calculated based on the _current_ on-chain fees.
This value is called `miner_fee` in the gRPC/REST responses.
- **Max on-chain sweep fee** (14900 sat): The maximum on-chain fee the daemon
is going to allow for sweeping the HTLC in case of success. A fee estimation
based on the `--conf_target` flag is always performed before sweeping. The
factor of `100` times the estimated fee is applied in case the fees spike
between the time the swap is initiated and the time the HTLC can be swept. But
that is the absolute worst-case fee that will be paid. If there is no fee
spike, a normal, much lower fee will be used.
- **Max off-chain swap routing fee** (20010 sat): The maximum off-chain
routing fee that the daemon should pay when finding a route to pay the
Lightning invoice. This is a hard limit. If no route with a lower or equal fee
is found, the payment (and the swap) is aborted. This value is calculated
statically based on the swap amount (see `maxRoutingFeeBase` and
`maxRoutingFeeRate` in `cmd/loop/main.go`).
- **Max off-chain prepay routing fee** (36 sat): The maximum off-chain routing
fee that the daemon should pay when finding a route to pay the prepay fee.
This is a hard limit. If no route with a lower or equal fee is found, the
payment (and the swap) is aborted. This value is calculated statically based
on the prepay amount (see `maxRoutingFeeBase` and `maxRoutingFeeRate` in
`cmd/loop/main.go`).
- **Max no show penalty (prepay)** (1337 sat): This is the amount that has to be
pre-paid (off-chain) before the server publishes the HTLC on-chain. This is
necessary to ensure the server's on-chain fees are paid if the client aborts
and never completes the swap _after_ the HTLC has been published on-chain.
If the swap completes normally, this amount is counted towards the full swap
amount and therefore is actually a pre-payment and not a fee. This value is
called `prepay_amt` in the gRPC/REST responses.
- **Max swap fee** (1100 sat): The maximum amount of service fees we allow the
server to charge for executing the swap. The client aborts the swap if the
fee proposed by the server exceeds this maximum. It is therefore recommended
to obtain the maximum by asking the server for a quote first. The actual fees
might be lower than this maximum if user specific discounts are applied. This
value is called `swap_fee` in the gRPC/REST responses.
#### Fast vs. batched swaps
By default, Loop Outs are executed as normal speed swaps. This means the server
will wait up to 30 minutes until it publishes the HTLC on-chain to improve the
chances that it can be batched together with other user's swaps to reduce the
on-chain footprint and fees. The server offers a reduced swap fee for slow swaps
to incentivize users to batch more.
If a swap should be executed immediately, the `--fast` flag can be used. Fast
swaps won't benefit from a reduced swap fee.
### Loop In Swaps
Additionally, Loop In is now also supported for mainnet as well. A Loop In swap
@ -195,9 +271,10 @@ DESCRIPTION:
Send the amount in satoshis specified by the amt argument off-chain.
OPTIONS:
--amt value the amount in satoshis to loop in (default: 0)
--external expect htlc to be published externally
--conf_target the confirmation target for the on chain htlc, if not being published externally
--amt value the amount in satoshis to loop in (default: 0)
--external expect htlc to be published externally
--conf_target value the target number of blocks the on-chain htlc broadcast by the swap client should confirm within (default: 0)
--last_hop value the pubkey of the last hop to use for this swap
```
The `--external` argument allows the on-chain HTLC transacting to be published
@ -208,6 +285,34 @@ A Loop In swap can be executed a follows:
```
loop in <amt_in_satoshis>
```
#### Fees explained
The following is an example output of a 0.01 BTC Loop In swap from `testnet`:
```bash
$ loop in --amt 1000000
Max swap fees for 1000000 sat Loop In: 1562 sat
CONTINUE SWAP? (y/n), expand fee detail (x): x
Estimated on-chain HTLC fee: 154 sat
Max swap fee: 1100 sat
CONTINUE SWAP? (y/n):
```
Explanation:
- **Estimated on-chain HTLC fee** (154 sat): The estimated on-chain fee that the
daemon has to pay to publish the HTLC. This is an estimation from `lnd`'s
wallet based on the available UTXOs and current network fees. This value is
called `miner_fee` in the gRPC/REST responses.
- **Max swap fee** (1100 sat): The maximum amount of service fees we allow the
server to charge for executing the swap. The client aborts the swap if the
fee proposed by the server exceeds this maximum. It is therefore recommended
to obtain the maximum by asking the server for a quote first. The actual fees
might be lower than this maximum if user specific discounts are applied. This
value is called `swap_fee` in the gRPC/REST responses.
## Resume
When `loopd` is terminated (or killed) for whatever reason, it will pickup
@ -220,4 +325,3 @@ Its location is `~/.loopd/<network>/loop.db`.
It is possible to execute multiple swaps simultaneously. Just keep loopd
Oliver Gugger
4 years ago