MEV-Boost Relay for Ethereum proposer/builder separation (PBS).
Currently live at:
- https://boost-relay.flashbots.net (also on Goerli and Sepolia)
- https://relay.ultrasound.money
- https://agnostic-relay.net
- bloXroute relays (running a light fork)
- https://mainnet.aestus.live
- https://relayooor.wtf
- https://relay.edennetwork.io/info
- https://mainnet-relay.securerpc.com
The relay consists of several components that are designed to run and scale independently and to be as simple as possible:
- API: for proposer, block builder, data.
- Website: handles the root website requests (information is pulled from Redis and database).
- Housekeeper: update known validators, proposer duties.
- Redis
- PostgreSQL
- one or more beacon nodes
- block submission validation nodes
- [optional] Memcached
- The relay services need access to one or more beacon node for event subscriptions (in particular the
head
andpayload_attributes
topics). - You can specify multiple beacon nodes by providing a comma separated list of beacon node URIs.
- The beacon nodes need to support the []
payload_attributes
SSE event](ethereum/beacon-APIs#305). - As of now, this is either:
- Lighthouse v4.0.1+ (with
--always-prepare-payload
and--prepare-payload-lookahead 12000
flags, and some junk feeRecipeint), with the validate-before-broadcast patch. Here's a quick guide for setting up Lighthouse. - Prysm v4.0.0+ with the validate-before-broadcast patch or the more experimental fast-validate-before-broadcast patch
- Lighthouse v4.0.1+ (with
Relays are strongly advised to run multiple beacon nodes!
- The reason is that on getPayload, the block has to be validated and broadcast by a local beacon node before it is returned to the proposer.
- If the local beacon nodes don't accept it (i.e. because it's down), the block won't be returned to the proposer, which leads to the proposer missing the slot.
- The relay makes the validate+broadcast request to all beacon nodes concurrently, and returns as soon as the first request is successful.
A security assessment for the relay was conducted on 2022-08-22 by lotusbumi. Additional information can be found in the Security section of this repository.
If you find a security vulnerability on this project or any other initiative related to Flashbots, please let us know sending an email to [email protected].
MEV is a centralizing force on Ethereum. Unattended, the competition for MEV opportunities leads to consensus security instability and permissioned communication infrastructure between traders and block producers. This erodes neutrality, transparency, decentralization, and permissionlessness.
Flashbots is a research and development organization working on mitigating the negative externalities of MEV. Flashbots started as a builder specializing in MEV extraction in proof-of-work Ethereum to democratize access to MEV and make the most profitable blocks available to all miners. >90% of miners are outsourcing some of their block construction to Flashbots today.
The mev-boost relay is a trusted mediator between block producers and block builders. It enables all Ethereum proof-of-stake validators to offer their blockspace to not just Flashbots but other builders as well. This opens up the market to more builders and creates competition between them, leading to more revenue and choice for validators, and better censorship-resistance for Ethereum.
In the future, proposer/builder separation will be enshrined in the Ethereum protocol itself to further harden its trust model.
Read more in Why run mev-boost? and in the Frequently Asked Questions.
# Start PostgreSQL & Redis individually:
docker run -d -p 5432:5432 -e POSTGRES_USER=postgres -e POSTGRES_PASSWORD=postgres -e POSTGRES_DB=postgres postgres
docker run -d -p 6379:6379 redis
# [optional] Start Memcached
docker run -d -p 11211:11211 memcached
# Or with docker-compose:
docker-compose up
Note: docker-compose also runs an Adminer (a web frontend for Postgres) on http://localhost:8093/?username=postgres (db: postgres
, username: postgres
, password: postgres
)
Now start the services:
# The housekeeper sets up the validators, and does various housekeeping
go run . housekeeper --network sepolia --db postgres://postgres:postgres@localhost:5432/postgres?sslmode=disable
# Run APIs for sepolia (using a dummy BLS secret key)
go run . api --network sepolia --secret-key 0x607a11b45a7219cc61a3d9c5fd08c7eebd602a6a19a977f8d3771d5711a550f2 --db postgres://postgres:postgres@localhost:5432/postgres?sslmode=disable
# Run Website for sepolia
go run . website --network sepolia --db postgres://postgres:postgres@localhost:5432/postgres?sslmode=disable
# Query status
curl localhost:9062/eth/v1/builder/status
# Send test validator registrations
curl -X POST localhost:9062/eth/v1/builder/validators -d @testdata/valreg2.json
# Delete previous registrations
redis-cli DEL boost-relay/sepolia:validators-registration boost-relay/sepolia:validators-registration-timestamp
ACTIVE_VALIDATOR_HOURS
- number of hours to track active proposers in redis (default: 3)API_TIMEOUT_READ_MS
- http read timeout in milliseconds (default: 1500)API_TIMEOUT_READHEADER_MS
- http read header timeout in milliseconds (default: 600)API_TIMEOUT_WRITE_MS
- http write timeout in milliseconds (default: 10000)API_TIMEOUT_IDLE_MS
- http idle timeout in milliseconds (default: 3000)API_MAX_HEADER_BYTES
- http maximum header byted (default: 60kb)BLOCKSIM_MAX_CONCURRENT
- maximum number of concurrent block-sim requests (0 for no maximum, default: 4)BLOCKSIM_TIMEOUT_MS
- builder block submission validation request timeout (default: 3000)DB_DONT_APPLY_SCHEMA
- disable applying DB schema on startup (useful for connecting data API to read-only replica)DB_TABLE_PREFIX
- prefix to use for db tables (default usesdev
)GETPAYLOAD_RETRY_TIMEOUT_MS
- getPayload retry getting a payload if first try failed (default: 100)MEMCACHED_URIS
- optional comma separated list of memcached endpoints, typically used as secondary storage alongside RedisMEMCACHED_EXPIRY_SECONDS
- item expiry timeout when using memcache (default: 45)MEMCACHED_CLIENT_TIMEOUT_MS
- client timeout in milliseconds (default: 250)MEMCACHED_MAX_IDLE_CONNS
- client max idle conns (default: 10)NUM_ACTIVE_VALIDATOR_PROCESSORS
- proposer API - number of goroutines to listen to the active validators channelNUM_VALIDATOR_REG_PROCESSORS
- proposer API - number of goroutines to listen to the validator registration channel
DISABLE_PAYLOAD_DATABASE_STORAGE
- builder API - disable storing execution payloads in the database (i.e. when using memcached as data availability redundancy)DISABLE_LOWPRIO_BUILDERS
- reject block submissions by low-prio buildersFORCE_GET_HEADER_204
- force 204 as getHeader responseMEMCACHE_ALLOW_SAVING_FAIL
-- don't abort builder submission if memcache saving fails
RUN_DB_TESTS
- when set to "1" enables integration tests with Postgres using endpoint specified by environment variableTEST_DB_DSN
RUN_INTEGRATION_TESTS
- when set to "1" enables integration tests, currently used for testing Memcached using comma separated list of endpoints specified byMEMCACHED_URIS
TEST_DB_DSN
- specifies connection string using Data Source Name (DSN) for Postgres (default: postgres://postgres:postgres@localhost:5432/postgres?sslmode=disable)
- Edit the HTML in
services/website/website.html
- Edit template values in
testdata/website-htmldata.json
- Generate a static version of the website with
go run scripts/website-staticgen/main.go
This builds a local copy of the template and saves it in website-index.html
The website is using:
See ARCHITECTURE.md and Running MEV-Boost-Relay at scale for more technical details!
By default, the execution payloads for all block submission are stored in Redis and also in the Postgres database,
to provide redundant data availability for getPayload responses. But the database table is not pruned automatically,
because it takes a lot of resources to rebuild the indexes (and a better option is using TRUNCATE
).
Storing all the payloads in the database can lead to terrabytes of data in this particular table. Now it's also possible to use memcached as a second data availability layer. Using memcached is optional and disabled by default.
To enable memcached, you just need to supply the memcached URIs either via environment variable (i.e.
MEMCACHED_URIS=localhost:11211
) or through command line flag (--memcached-uris
).
You can disable storing the execution payloads in the database with this environment variable:
DISABLE_PAYLOAD_DATABASE_STORAGE=1
.
You can use the builder project to validate block builder submissions: https://github.com/flashbots/builder
Here's an example systemd config:
/etc/systemd/system/geth.service
[Unit]
Description=mev-boost
Wants=network-online.target
After=network-online.target
[Service]
User=ubuntu
Group=ubuntu
Environment=HOME=/home/ubuntu
Type=simple
KillMode=mixed
KillSignal=SIGINT
TimeoutStopSec=90
Restart=on-failure
RestartSec=10s
ExecStart=/home/ubuntu/builder/build/bin/geth \
--syncmode=snap \
--datadir /var/lib/goethereum \
--metrics \
--metrics.expensive \
--http \
--http.api="engine,eth,web3,net,debug,flashbots" \
--http.corsdomain "*" \
--http.addr "0.0.0.0" \
--http.port 8545 \
--http.vhosts '*' \
--ws \
--ws.api="engine,eth,web3,net,debug" \
--ws.addr 0.0.0.0 \
--ws.port 8546 \
--ws.api engine,eth,net,web3 \
--ws.origins '*' \
--graphql \
--graphql.corsdomain '*' \
--graphql.vhosts '*' \
--authrpc.addr="0.0.0.0" \
--authrpc.jwtsecret=/var/lib/goethereum/jwtsecret \
--authrpc.vhosts '*' \
--cache=8192
[Install]
WantedBy=multi-user.target
Sending blocks to the validation node:
- The built-in blocksim-ratelimiter is a simple example queue implementation.
- By default,
BLOCKSIM_MAX_CONCURRENT
is set to 4, which allows 4 concurrent block simulations per API node - For production use, use the prio-load-balancer project for a single priority queue,
and disable the internal concurrency limit (set
BLOCKSIM_MAX_CONCURRENT
to0
).
- Use Lighthouse v4.0.1+
- with
--always-prepare-payload
and--prepare-payload-lookahead 12000
flags, and some junk feeRecipeint - use the validate-before-broadcast patch
Here's a quick guide for setting up Lighthouse.
Here's an example Lighthouse systemd config:
/etc/systemd/system/lighthouse.service
[Unit]
Description=Lighthouse
After=network.target
Wants=network.target
[Service]
User=ubuntu
Group=ubuntu
Type=simple
Restart=always
RestartSec=5
TimeoutStopSec=180
ExecStart=/home/ubuntu/.cargo/bin/lighthouse bn \
--network mainnet \
--checkpoint-sync-url=https://mainnet-checkpoint-sync.attestant.io \
--eth1 \
--http \
--http-address "0.0.0.0" \
--http-port 3500 \
--datadir=/mnt/data/lighthouse \
--http-allow-sync-stalled \
--execution-endpoints=http://localhost:8551 \
--jwt-secrets=/var/lib/goethereum/jwtsecret \
--disable-deposit-contract-sync \
--always-prepare-payload \
--prepare-payload-lookahead 12000
[Install]
WantedBy=default.target
- Prysm v4.0.0+
- with this validate-before-broadcast patch or the more experimental fast-validate-before-broadcast patch
- use
--grpc-max-msg-size 104857600
, because by default the getAllValidators response is too big and fails
Here's an example Prysm systemd config:
/etc/systemd/system/prysm.service
[Unit]
Description=Prysm
After=network.target
Wants=network.target
[Service]
User=ubuntu
Group=ubuntu
Type=simple
Restart=always
RestartSec=5
TimeoutStopSec=180
ExecStart=/home/ubuntu/prysm/bazel-bin/cmd/beacon-chain/beacon-chain_/beacon-chain \
--accept-terms-of-use \
--enable-debug-rpc-endpoints \
--checkpoint-sync-url=https://mainnet-checkpoint-sync.attestant.io \
--genesis-beacon-api-url=https://mainnet-checkpoint-sync.attestant.io \
--grpc-gateway-host "0.0.0.0" \
--datadir=/mnt/data/prysm \
--p2p-max-peers 100 \
--execution-endpoint=http://localhost:8551 \
--jwt-secret=/var/lib/goethereum/jwtsecret \
--min-sync-peers=1 \
--grpc-max-msg-size 104857600
[Install]
WantedBy=default.target
Flashbots is a research and development collective working on mitigating the negative externalities of decentralized economies. We contribute with the larger free software community to illuminate the dark forest.
You are welcome here <3.
- If you have a question, feedback or a bug report for this project, please open a new Issue.
- If you would like to contribute with code, check the CONTRIBUTING file for further info about the development environment.
- We just ask you to be nice. Read our code of conduct.
If you find a security vulnerability on this project or any other initiative related to Flashbots, please let us know sending an email to [email protected].
The code in this project is free software under the AGPL License version 3 or later.
Made with ☀️ by the ⚡🤖 collective.