Compatibility with Teku VC for voluntary-exit

[heejin-github]

Description

I'm using LightHouse BN, and validator operated with Teku VC client.
If I'm trying to voluntary exit with Teku VC client, it was failed to retrieve network spec constant MAX_REQUEST_BLOCKS from beacon node endpoint as below. but, LightHouse BN didn't provide it.
Teku seems to check network spec configuration before run voluntary exit.

• Teku log,

Loading configuration...
Failed to retrieve network spec from beacon node endpoint 'http://127.0.0.1:3600/'.
Details: Missing value for spec constant 'MAX_REQUEST_BLOCKS'

Version

Lighthouse BN : v4.4.1
Teku VC : v23.9.0

Present Behaviour

LightHouse BN didn't provide MAX_REQUEST_BLOCKS via beacon API. /eth/v1/config/spec

# curl -s localhost:5052/eth/v1/config/spec | jq
{
  "data": {
    "CONFIG_NAME": "prater",
    "PRESET_BASE": "mainnet",
    "TERMINAL_TOTAL_DIFFICULTY": "10790000",
    "TERMINAL_BLOCK_HASH": "0x0000000000000000000000000000000000000000000000000000000000000000",
    "TERMINAL_BLOCK_HASH_ACTIVATION_EPOCH": "18446744073709551615",
    "SAFE_SLOTS_TO_IMPORT_OPTIMISTICALLY": "128",
    "MIN_GENESIS_ACTIVE_VALIDATOR_COUNT": "16384",
    "MIN_GENESIS_TIME": "1614588812",
    "GENESIS_FORK_VERSION": "0x00001020",
    "GENESIS_DELAY": "1919188",
    "ALTAIR_FORK_VERSION": "0x01001020",
    "ALTAIR_FORK_EPOCH": "36660",
    "BELLATRIX_FORK_VERSION": "0x02001020",
    "BELLATRIX_FORK_EPOCH": "112260",
    "CAPELLA_FORK_VERSION": "0x03001020",
    "CAPELLA_FORK_EPOCH": "162304",
    "SECONDS_PER_SLOT": "12",
    "SECONDS_PER_ETH1_BLOCK": "14",
    "MIN_VALIDATOR_WITHDRAWABILITY_DELAY": "256",
    "SHARD_COMMITTEE_PERIOD": "256",
    "ETH1_FOLLOW_DISTANCE": "2048",
    "SUBNETS_PER_NODE": "2",
    "INACTIVITY_SCORE_BIAS": "4",
    "INACTIVITY_SCORE_RECOVERY_RATE": "16",
    "EJECTION_BALANCE": "16000000000",
    "MIN_PER_EPOCH_CHURN_LIMIT": "4",
    "CHURN_LIMIT_QUOTIENT": "65536",
    "PROPOSER_SCORE_BOOST": "40",
    "DEPOSIT_CHAIN_ID": "5",
    "DEPOSIT_NETWORK_ID": "5",
    "DEPOSIT_CONTRACT_ADDRESS": "0xff50ed3d0ec03ac01d4c79aad74928bff48a7b2b",
    "GOSSIP_MAX_SIZE": "10485760",
    "MIN_EPOCHS_FOR_BLOCK_REQUESTS": "33024",
    "MAX_CHUNK_SIZE": "10485760",
    "TTFB_TIMEOUT": "5",
    "RESP_TIMEOUT": "10",
    "MESSAGE_DOMAIN_INVALID_SNAPPY": "0x00000000",
    "MESSAGE_DOMAIN_VALID_SNAPPY": "0x01000000",
    "ATTESTATION_SUBNET_EXTRA_BITS": "0",
    "ATTESTATION_SUBNET_PREFIX_BITS": "6",
    "MAX_COMMITTEES_PER_SLOT": "64",
    "TARGET_COMMITTEE_SIZE": "128",
    "MAX_VALIDATORS_PER_COMMITTEE": "2048",
    "SHUFFLE_ROUND_COUNT": "90",
    "HYSTERESIS_QUOTIENT": "4",
    "HYSTERESIS_DOWNWARD_MULTIPLIER": "1",
    "HYSTERESIS_UPWARD_MULTIPLIER": "5",
    "SAFE_SLOTS_TO_UPDATE_JUSTIFIED": "8",
    "MIN_DEPOSIT_AMOUNT": "1000000000",
    "MAX_EFFECTIVE_BALANCE": "32000000000",
    "EFFECTIVE_BALANCE_INCREMENT": "1000000000",
    "MIN_ATTESTATION_INCLUSION_DELAY": "1",
    "SLOTS_PER_EPOCH": "32",
    "MIN_SEED_LOOKAHEAD": "1",
    "MAX_SEED_LOOKAHEAD": "4",
    "EPOCHS_PER_ETH1_VOTING_PERIOD": "64",
    "SLOTS_PER_HISTORICAL_ROOT": "8192",
    "MIN_EPOCHS_TO_INACTIVITY_PENALTY": "4",
    "EPOCHS_PER_HISTORICAL_VECTOR": "65536",
    "EPOCHS_PER_SLASHINGS_VECTOR": "8192",
    "HISTORICAL_ROOTS_LIMIT": "16777216",
    "VALIDATOR_REGISTRY_LIMIT": "1099511627776",
    "BASE_REWARD_FACTOR": "64",
    "WHISTLEBLOWER_REWARD_QUOTIENT": "512",
    "PROPOSER_REWARD_QUOTIENT": "8",
    "INACTIVITY_PENALTY_QUOTIENT": "67108864",
    "MIN_SLASHING_PENALTY_QUOTIENT": "128",
    "PROPORTIONAL_SLASHING_MULTIPLIER": "1",
    "MAX_PROPOSER_SLASHINGS": "16",
    "MAX_ATTESTER_SLASHINGS": "2",
    "MAX_ATTESTATIONS": "128",
    "MAX_DEPOSITS": "16",
    "MAX_VOLUNTARY_EXITS": "16",
    "INACTIVITY_PENALTY_QUOTIENT_ALTAIR": "50331648",
    "MIN_SLASHING_PENALTY_QUOTIENT_ALTAIR": "64",
    "PROPORTIONAL_SLASHING_MULTIPLIER_ALTAIR": "2",
    "SYNC_COMMITTEE_SIZE": "512",
    "EPOCHS_PER_SYNC_COMMITTEE_PERIOD": "256",
    "MIN_SYNC_COMMITTEE_PARTICIPANTS": "1",
    "INACTIVITY_PENALTY_QUOTIENT_BELLATRIX": "16777216",
    "MIN_SLASHING_PENALTY_QUOTIENT_BELLATRIX": "32",
    "PROPORTIONAL_SLASHING_MULTIPLIER_BELLATRIX": "3",
    "MAX_BYTES_PER_TRANSACTION": "1073741824",
    "MAX_TRANSACTIONS_PER_PAYLOAD": "1048576",
    "BYTES_PER_LOGS_BLOOM": "256",
    "MAX_EXTRA_DATA_BYTES": "32",
    "MAX_BLS_TO_EXECUTION_CHANGES": "16",
    "MAX_WITHDRAWALS_PER_PAYLOAD": "16",
    "MAX_VALIDATORS_PER_WITHDRAWALS_SWEEP": "16384",
    "BLS_WITHDRAWAL_PREFIX": "0x00",
    "DOMAIN_BEACON_ATTESTER": "0x01000000",
    "DOMAIN_RANDAO": "0x02000000",
    "DOMAIN_AGGREGATE_AND_PROOF": "0x06000000",
    "DOMAIN_SYNC_COMMITTEE_SELECTION_PROOF": "0x08000000",
    "TARGET_AGGREGATORS_PER_COMMITTEE": "16",
    "DOMAIN_SELECTION_PROOF": "0x05000000",
    "DOMAIN_SYNC_COMMITTEE": "0x07000000",
    "DOMAIN_BEACON_PROPOSER": "0x00000000",
    "DOMAIN_VOLUNTARY_EXIT": "0x04000000",
    "DOMAIN_APPLICATION_MASK": "0x00000001",
    "DOMAIN_CONTRIBUTION_AND_PROOF": "0x09000000",
    "TARGET_AGGREGATORS_PER_SYNC_SUBCOMMITTEE": "16",
    "DOMAIN_DEPOSIT": "0x03000000",
    "SYNC_COMMITTEE_SUBNET_COUNT": "4"
  }
}

Expected Behaviour

Provide MAX_REQUEST_BLOCKS constant value through beacon API /eth/v1/config/spec

Steps to resolve

Need to provide MAX_REQUEST_BLOCKS constant value for voluntary-exit with Teku VC Client.

[michaelsproul]

Hey @heejin-github thanks for bringing this to our attention. Lighthouse generally updates the /config/spec at each hard-fork, and the field MAX_REQUEST_BLOCKS was not added as part of a hard fork (it was added in this PR: ethereum/consensus-specs#3375).

You might be able to work around the issue by using an older version of Teku that doesn't expect this field. It's my opinion that Teku shouldn't be so strict here, but we can also fix it on our side for the next release.

[heejin-github]

Hey @michaelsproul
yeah, make sense for me. I'll close this issue. and I look forward to fix it for the next release.
Thank you for your efforts in client diversity and compatibility.

[michaelsproul]

I'll leave it open so we can track it

[duguorong009]

Hey, @michaelsproul @paulhauner
I think this issue needs to be addressed, since v4.5.0 is released.
Hence, I created the PR addressing the issue.
Please check the PR #4800 & gimme the comments.

[michaelsproul]

Closing this issue in favour of #4562. The Teku-incompatibility has been addressed on Teku's side, and Lighthouse will include the value on the spec endpoint once #4562 is solved.