* Support for driving multiple EL nodes from a single Nimbus BN
Full list of changes:
* Eth1Monitor has been renamed to ELManager to match its current
responsibilities better.
* The ELManager is no longer optional in the code (it won't have
a nil value under any circumstances).
* The support for subscribing for headers was removed as it only
worked with WebSockets and contributed significant complexity
while bringing only a very minor advantage.
* The `--web3-url` parameter has been deprecated in favor of a
new `--el` parameter. The new parameter has a reasonable default
value and supports specifying a different JWT for each connection.
Each connection can also be configured with a different set of
responsibilities (e.g. download deposits, validate blocks and/or
produce blocks). On the command-line, these properties can be
configured through URL properties stored in the #anchor part of
the URL. In TOML files, they come with a very natural syntax
(althrough the URL scheme is also supported).
* The previously scattered EL-related state and logic is now moved
to `eth1_monitor.nim` (this module will be renamed to `el_manager.nim`
in a follow-up commit). State is assigned properly either to the
`ELManager` or the to individual `ELConnection` objects where
appropriate.
The ELManager executes all Engine API requests against all attached
EL nodes, in parallel. It compares their results and if there is a
disagreement regarding the validity of a certain payload, this is
detected and the beacon node is protected from publishing a block
with a potential execution layer consensus bug in it.
The BN provides metrics per EL node for the number of successful or
failed requests for each type Engine API requests. If an EL node
goes offline and connectivity is resoted later, we report the
problem and the remedy in edge-triggered fashion.
* More progress towards implementing Deneb block production in the VC
and comparing the value of blocks produced by the EL and the builder
API.
* Adds a Makefile target for the zhejiang testnet
The optimistic sync spec was updated since the LC based optsync module
was introduced. It is no longer necessary to wait for the justified
checkpoint to have execution enabled; instead, any block is okay to be
optimistically imported to the EL client, as long as its parent block
has execution enabled. Complex syncing logic has been removed, and the
LC optsync module will now follow gossip directly, reducing the latency
when using this module. Note that because this is now based on gossip
instead of using sync manager / request manager, that individual blocks
may be missed. However, EL clients should recover from this by fetching
missing blocks themselves.
Adds the `--web3-url` launch argument to `nimbus_light_client` to enable
driving the EL with the optimistic head obtained from LC sync protocol.
This will keep issuing `newPayload` / `forkChoiceUpdated` requests for
new blocks, marking them as optimistic. `ZERO_HASH` is reported as the
finalized block for now.
Adds a `LightClient` instance to the beacon node as preparation to
accelerate syncing in the future (optimistic sync).
- `--light-client-enable` turns on the feature
- `--light-client-trusted-block-root` configures block to start from
If no block root is configured, light client tracks DAG `finalizedHead`.
Introduces a new library for syncing using libp2p based light client
sync protocol, and adds a new `nimbus_light_client` executable that uses
this library for syncing. The new executable emits log messages when
new beacon block headers are received, and is integrated into testing.
zah
tersec
Etan Kissling
Miran