From: Christian Decker <decker.christian@gmail.com>
To: Brian Lockhart <brianlockhart@gmail.com>,
	Kulpreet Singh <zapfmann@gmail.com>,
	Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>,
	Patrick Shirkey <pshirkey@boosthardware.com>
In-Reply-To: <CAJQ0i9v0T8w4LD13z9AePtgnMdiG7=1pjMFWVXTnCFRVB1bwpw@mail.gmail.com>
References: <fd403450-cf7f-ce56-79ca-93c77c042289@frankentrikes.com>
	<0cc0a7249708ad26a7cbef702370b234.squirrel@boosthardware.com>
	<CAN8S4uarZ39BqpmZQqqoof6nDXH7eSuH1rT03ABX2x-Gzc9sXg@mail.gmail.com>
	<87fu1qdd5e.fsf@gmail.com>
	<CAJQ0i9v0T8w4LD13z9AePtgnMdiG7=1pjMFWVXTnCFRVB1bwpw@mail.gmail.com>
Date: Wed, 13 Jun 2018 18:17:20 +0200
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Subject: Re: [bitcoin-dev] Why not archive the backend of Bitcoin blockchain?
Precedence: list

Brian Lockhart <brianlockhart@gmail.com> writes:
> In the interest of avoiding running multiple bitcoind full nodes - is the=
re
> a method to allow a Lightning node to point to / access a separate
> already-existing node, vs. requiring it to have its own dedicated local
> instance of bitcoind running?
>
> I.e. if I already have a full bitcoin node running, could I use RPC calls
> or something to tell my Lightning node to use that node, instead of
> spinning up *another* full node? I=E2=80=99m currently minimizing the net=
work
> thrashing by whitelisting my LN bitcoind node to only point to my existing
> full node for updates, but if I could just point my whole LN node at it,
> that=E2=80=99s save on disk storage etc. etc. etc.

Certainly, that's supported by all 3 implementations:

 - With c-lightning you can either configure `bitcoin-cli` to connect to
   a remote node with the `rpcconnect`, `rpcuser`, and `rpcpassword`
   options in the `bitcoin.conf` file (at which point all calls to
   `bitcoin-cli` will use that node) or you can use the following
   command line options when starting `lightningd`: `--bitcoin-rpcuser`,
   `--bitcoin-rpcpassword` and `--bitcoin-rpcconnect`
 - lnd allows you to specify the node to connect to using the command
   line options `--bitcoind.rpchost`, `--bitcoind.rpcuser`, and
   `--bitcoind.rpcpass`.
 - Eclair requires you to edit the configuration file [1] before
   compiling afaik

Cheers,
Christian


[1] https://github.com/ACINQ/eclair/blob/master/eclair-core/src/main/resour=
ces/reference.conf