Configs

In order to specify a config for the C-Chain, a JSON config file should be placed at {chain-config-dir}/C/config.json. This file does not exist by default.

For example if chain-config-dir has the default value which is $HOME/.avalanchego/configs/chains, then config.json should be placed at $HOME/.avalanchego/configs/chains/C/config.json.

The C-Chain config is printed out in the log when a node starts. Default values for each config flag are specified below.

Default values are overridden only if specified in the given config file. It is recommended to only provide values which are different from the default, as that makes the config more resilient to future default changes. Otherwise, if defaults change, your node will remain with the old values, which might adversely affect your node operation.

State Sync

state-sync-enabled

Boolean

Set to true to start the chain with state sync enabled. The peer will download chain state from peers up to a recent block near tip, then proceed with normal bootstrapping.

Defaults to perform state sync if starting a new node from scratch. However, if running with an existing database it will default to false and not perform state sync on subsequent runs.

Please note that if you need historical data, state sync isn't the right option. However, it is sufficient if you are just running a validator.

state-sync-skip-resume

Boolean

If set to true, the chain will not resume a previously started state sync operation that did not complete. Normally, the chain should be able to resume state syncing without any issue. Defaults to false.

state-sync-min-blocks

Integer

Minimum number of blocks the chain should be ahead of the local node to prefer state syncing over bootstrapping. If the node's database is already close to the chain's tip, bootstrapping is more efficient. Defaults to 300000.

state-sync-ids

String

Comma separated list of node IDs (prefixed with NodeID-) to fetch state sync data from. An example setting of this field would be --state-sync-ids="NodeID-7Xhw2mDxuDS44j42TCB6U5579esbSt3Lg,NodeID-MFrZFVCXPv5iCn6M9K6XduxGTYp891xXZ". If not specified (or empty), peers are selected at random. Defaults to empty string ("").

state-sync-server-trie-cache

Integer

Size of trie cache used for providing state sync data to peers in MBs. Should be a multiple of 64. Defaults to 64.

Continuous Profiling

continuous-profiler-dir

String

Enables the continuous profiler (captures a CPU/Memory/Lock profile at a specified interval). Defaults to "". If a non-empty string is provided, it enables the continuous profiler and specifies the directory to place the profiles in.

continuous-profiler-frequency

Duration

Specifies the frequency to run the continuous profiler. Defaults 900000000000 nano seconds which is 15 minutes.

continuous-profiler-max-files

Integer

Specifies the maximum number of profiles to keep before removing the oldest. Defaults to 5.

Enabling Avalanche Specific APIs

snowman-api-enabled

Boolean

Enables the Snowman API. Defaults to false.

coreth-admin-api-enabled

Boolean

Deprecated as of v0.12.5. Use admin-api-enabled instead.

Enables the Admin API. Defaults to false.

coreth-admin-api-dir

String

Deprecated as of v0.12.5. Use admin-api-dir instead.

Specifies the directory for the Admin API to use to store CPU/Mem/Lock Profiles. Defaults to "".

Enabling EVM APIs

eth-apis ([]string)

Use the eth-apis field to specify the exact set of below services to enable on your node. If this field is not set, then the default list will be: ["eth","eth-filter","net","web3","internal-eth","internal-blockchain","internal-transaction"].

eth

The API name public-eth is deprecated as of v1.7.15, and the APIs previously under this name have been migrated to eth.

Adds the following RPC calls to the eth_* namespace. Defaults to true.

eth_coinbase eth_etherbase

eth-filter

The API name public-eth-filter is deprecated as of v1.7.15, and the APIs previously under this name have been migrated to eth-filter.

Enables the public filter API for the eth_* namespace. Defaults to true.

Adds the following RPC calls (see here for complete documentation):

• eth_newPendingTransactionFilter
• eth_newPendingTransactions
• eth_newAcceptedTransactions
• eth_newBlockFilter
• eth_newHeads
• eth_logs
• eth_newFilter
• eth_getLogs
• eth_uninstallFilter
• eth_getFilterLogs
• eth_getFilterChanges

admin

The API name private-admin is deprecated as of v1.7.15, and the APIs previously under this name have been migrated to admin.

Adds the following RPC calls to the admin_* namespace. Defaults to false.

• admin_importChain
• admin_exportChain

debug

The API names private-debug and public-debug are deprecated as of v1.7.15, and the APIs previously under these names have been migrated to debug.

Adds the following RPC calls to the debug_* namespace. Defaults to false.

• debug_dumpBlock
• debug_accountRange
• debug_preimage
• debug_getBadBlocks
• debug_storageRangeAt
• debug_getModifiedAccountsByNumber
• debug_getModifiedAccountsByHash
• debug_getAccessibleState

net

Adds the following RPC calls to the net_* namespace. Defaults to true.

• net_listening
• net_peerCount
• net_version

Note: Coreth is a virtual machine and does not have direct access to the networking layer, so net_listening always returns true and net_peerCount always returns 0. For accurate metrics on the network layer, users should use the AvalancheGo APIs.

debug-tracer

Adds the following RPC calls to the debug_* namespace. Defaults to false.

• debug_traceChain
• debug_traceBlockByNumber
• debug_traceBlockByHash
• debug_traceBlock
• debug_traceBadBlock
• debug_intermediateRoots
• debug_traceTransaction
• debug_traceCall

web3

Adds the following RPC calls to the web3_* namespace. Defaults to true.

• web3_clientVersion
• web3_sha3

internal-eth

The API name internal-public-eth is deprecated as of v1.7.15, and the APIs previously under this name have been migrated to internal-eth.

Adds the following RPC calls to the eth_* namespace. Defaults to true.

• eth_gasPrice
• eth_baseFee
• eth_maxPriorityFeePerGas
• eth_feeHistory

internal-blockchain

The API name internal-public-blockchain is deprecated as of v1.7.15, and the APIs previously under this name have been migrated to internal-blockchain.

Adds the following RPC calls to the eth_* namespace. Defaults to true.

• eth_chainId
• eth_blockNumber
• eth_getBalance
• eth_getProof
• eth_getHeaderByNumber
• eth_getHeaderByHash
• eth_getBlockByNumber
• eth_getBlockByHash
• eth_getUncleBlockByNumberAndIndex
• eth_getUncleBlockByBlockHashAndIndex
• eth_getUncleCountByBlockNumber
• eth_getUncleCountByBlockHash
• eth_getCode
• eth_getStorageAt
• eth_call
• eth_estimateGas
• eth_createAccessList

internal-transaction

The API name internal-public-transaction-pool is deprecated as of v1.7.15, and the APIs previously under this name have been migrated to internal-transaction.

Adds the following RPC calls to the eth_* namespace. Defaults to true.

• eth_getBlockTransactionCountByNumber
• eth_getBlockTransactionCountByHash
• eth_getTransactionByBlockNumberAndIndex
• eth_getTransactionByBlockHashAndIndex
• eth_getRawTransactionByBlockNumberAndIndex
• eth_getRawTransactionByBlockHashAndIndex
• eth_getTransactionCount
• eth_getTransactionByHash
• eth_getRawTransactionByHash
• eth_getTransactionReceipt
• eth_sendTransaction
• eth_fillTransaction
• eth_sendRawTransaction
• eth_sign
• eth_signTransaction
• eth_pendingTransactions
• eth_resend

internal-tx-pool

The API name internal-public-tx-pool is deprecated as of v1.7.15, and the APIs previously under this name have been migrated to internal-tx-pool.

Adds the following RPC calls to the txpool_* namespace. Defaults to false.

• txpool_content
• txpool_contentFrom
• txpool_status
• txpool_inspect

internal-debug

The API names internal-private-debug and internal-public-debug are deprecated as of v1.7.15, and the APIs previously under these names have been migrated to internal-debug.

Adds the following RPC calls to the debug_* namespace. Defaults to false.

• debug_getHeaderRlp
• debug_getBlockRlp
• debug_printBlock
• debug_chaindbProperty
• debug_chaindbCompact

debug-handler

Adds the following RPC calls to the debug_* namespace. Defaults to false.

• debug_verbosity
• debug_vmodule
• debug_backtraceAt
• debug_memStats
• debug_gcStats
• debug_blockProfile
• debug_setBlockProfileRate
• debug_writeBlockProfile
• debug_mutexProfile
• debug_setMutexProfileFraction
• debug_writeMutexProfile
• debug_writeMemProfile
• debug_stacks
• debug_freeOSMemory
• debug_setGCPercent

internal-account

The API name internal-public-account is deprecated as of v1.7.15, and the APIs previously under this name have been migrated to internal-account.

Adds the following RPC calls to the eth_* namespace. Defaults to true.

• eth_accounts

internal-personal

The API name internal-private-personal is deprecated as of v1.7.15, and the APIs previously under this name have been migrated to internal-personal.

Adds the following RPC calls to the personal_* namespace. Defaults to false.

• personal_listAccounts
• personal_listWallets
• personal_openWallet
• personal_deriveAccount
• personal_newAccount
• personal_importRawKey
• personal_unlockAccount
• personal_lockAccount
• personal_sendTransaction
• personal_signTransaction
• personal_sign
• personal_ecRecover
• personal_signAndSendTransaction
• personal_initializeWallet
• personal_unpair

API Configuration

rpc-gas-cap

Integer

The maximum gas to be consumed by an RPC Call (used in eth_estimateGas and eth_call). Defaults to 50,000,000.

rpc-tx-fee-cap

Integer

Global transaction fee (price * gaslimit) cap (measured in AVAX) for send-transaction variants. Defaults to 100.

api-max-duration

Duration

Maximum API call duration. If API calls exceed this duration, they will time out. Defaults to 0 (no maximum).

api-max-blocks-per-request

Integer

Maximum number of blocks to serve per getLogs request. Defaults to 0 (no maximum).

ws-cpu-refill-rate

Duration

The refill rate specifies the maximum amount of CPU time to allot a single connection per second. Defaults to no maximum (0).

ws-cpu-max-stored

Duration

Specifies the maximum amount of CPU time that can be stored for a single WS connection. Defaults to no maximum (0).

allow-unfinalized-queries

Allows queries for unfinalized (not yet accepted) blocks/transactions. Defaults to false.

accepted-cache-size

Integer

Specifies the depth to keep accepted headers and accepted logs in the cache. This is particularly useful to improve the performance of eth_getLogs for recent logs.

Transaction Pool

local-txs-enabled

Boolean

Enables local transaction handling (prioritizes transactions submitted through this node). Defaults to false.

allow-unprotected-txs

Boolean

If true, the APIs will allow transactions that are not replay protected (EIP-155) to be issued through this node. Defaults to false.

allow-unprotected-tx-hashes

[]TxHash

Specifies an array of transaction hashes that should be allowed to bypass replay protection. This flag is intended for node operators that want to explicitly allow specific transactions to be issued through their API. Defaults to an empty list.

push-gossip-percent-stake

Float

Percentage of the total stake to send transactions received over the RPC. Defaults to 0.9.

push-gossip-num-validators

Integer

Number of validators to initially send transactions received over the RPC. Defaults to 100.

push-gossip-num-peers

Integer

Number of peers to initially send transactions received over the RPC. Defaults to 0.

push-regossip-num-validators

Integer

Number of validators to periodically send transactions received over the RPC. Defaults to 10.

push-regossip-num-peers

Integer

Number of peers to periodically send transactions received over the RPC. Defaults to 0.

push-gossip-frequency

Duration

Frequency to send transactions received over the RPC to peers. Defaults to 100000000 nano seconds which is 100 milliseconds.

pull-gossip-frequency

Duration

Frequency to request transactions from peers. Defaults to 1000000000 nano seconds which is 1 second.

tx-regossip-frequency

Duration

Deprecated as of v0.12.5. Use regossip-frequency instead.

Amount of time that should elapse before we attempt to re-gossip a transaction that was already gossiped once. Defaults to 30000000000 nano seconds which is 30 seconds.

tx-pool-price-limit

Integer

Minimum gas price to enforce for acceptance into the pool. Defaults to 1 wei.

tx-pool-price-bump

Integer

Minimum price bump percentage to replace an already existing transaction (nonce). Defaults to 10%.

tx-pool-account-slots

Integer

Number of executable transaction slots guaranteed per account. Defaults to 16.

tx-pool-global-slots

Integer

Maximum number of executable transaction slots for all accounts. Defaults to 5120.

tx-pool-account-queue

Integer

Maximum number of non-executable transaction slots permitted per account. Defaults to 64.

tx-pool-global-queue

Integer

Maximum number of non-executable transaction slots for all accounts. Defaults to 1024.

tx-pool-lifetime

Duration

Maximum duration a non-executable transaction will be allowed in the poll. Defaults to 600000000000 nano seconds which is 10 minutes.

Metrics

metrics-enabled

Boolean

Enables metrics. Defaults to false.

metrics-expensive-enabled

Boolean

Enables expensive metrics. Defaults to false.

Snapshots

snapshot-async

Boolean

If true, allows snapshot generation to be executed asynchronously. Defaults to true.

snapshot-verification-enabled

Boolean

If true, verifies the complete snapshot after it has been generated. Defaults to false.

Logging

log-level

String

Defines the log level for the chain. Must be one of "trace", "debug", "info", "warn", "error", "crit". Defaults to "info".

log-json-format

Boolean

If true, changes logs to JSON format. Defaults to false.

Keystore Settings

keystore-directory

String

The directory that contains private keys. Can be given as a relative path. If empty, uses a temporary directory at coreth-keystore. Defaults to the empty string ("").

keystore-external-signer

String

Specifies an external URI for a clef-type signer. Defaults to the empty string ("" as not enabled).

keystore-insecure-unlock-allowed

Boolean

If true, allow users to unlock accounts in unsafe HTTP environment. Defaults to false.

Database

trie-clean-cache

Integer

Size of cache used for clean trie nodes (in MBs). Should be a multiple of 64. Defaults to 512.

trie-dirty-cache

Integer

Size of cache used for dirty trie nodes (in MBs). When the dirty nodes exceed this limit, they are written to disk. Defaults to 256.

trie-dirty-commit-target

Integer

Memory limit to target in the dirty cache before performing a commit (in MBs). Defaults to 20.

trie-prefetcher-parallelism

Integer

Max concurrent disk reads trie pre-fetcher should perform at once. Defaults to 16.

snapshot-cache

Integer

Size of the snapshot disk layer clean cache (in MBs). Should be a multiple of 64. Defaults to 256.

trie-clean-journal

String

Directory to use to save the trie clean cache (must be populated to enable journaling the trie clean cache). Empty and disabled by default.

trie-clean-rejournal

Duration

Frequency to re-journal the trie clean cache to disk (minimum 1 minute, must be populated to enable journaling the trie clean cache).

acceptor-queue-limit

Integer

Specifies the maximum number of blocks to queue during block acceptance before blocking on Accept. Defaults to 64.

commit-interval

Integer

Specifies the commit interval at which to persist the merkle trie to disk. Defaults to 4096.

pruning-enabled

Boolean

If true, database pruning of obsolete historical data will be enabled. This reduces the amount of data written to disk, but does not delete any state that is written to the disk previously. This flag should be set to false for nodes that need access to all data at historical roots. Pruning will be done only for new data. Defaults to false in v1.4.9, and true in subsequent versions.

populate-missing-tries

uint64

If non-nil, sets the starting point for repopulating missing tries to re-generate archival merkle forest.

To restore an archival merkle forest that has been corrupted (missing trie nodes for a section of the blockchain), specify the starting point of the last block on disk, where the full trie was available at that block to re-process blocks from that height onwards and re-generate the archival merkle forest on startup. This flag should be used once to re-generate the archival merkle forest and should be removed from the config after completion. This flag will cause the node to delay starting up while it re-processes old blocks.

populate-missing-tries-parallelism

Integer

Number of concurrent readers to use when re-populating missing tries on startup. Defaults to 1024.

allow-missing-tries

Boolean

If true, allows a node that was once configured as archival to switch to pruning mode. Defaults to false.

preimages-enabled

Boolean

If true, enables preimages. Defaults to false.

offline-pruning-enabled

Boolean

If true, offline pruning will run on startup and block until it completes (approximately one hour on Mainnet). This will reduce the size of the database by deleting old trie nodes. While performing offline pruning, your node will not be able to process blocks and will be considered offline. While ongoing, the pruning process consumes a small amount of additional disk space (for deletion markers and the bloom filter). For more information see here.

Since offline pruning deletes old state data, this should not be run on nodes that need to support archival API requests.

This is meant to be run manually, so after running with this flag once, it must be toggled back to false before running the node again. Therefore, you should run with this flag set to true and then set it to false on the subsequent run.

offline-pruning-bloom-filter-size

Integer

This flag sets the size of the bloom filter to use in offline pruning (denominated in MB and defaulting to 512 MB). The bloom filter is kept in memory for efficient checks during pruning and is also written to disk to allow pruning to resume without re-generating the bloom filter.

The active state is added to the bloom filter before iterating the DB to find trie nodes that can be safely deleted, any trie nodes not in the bloom filter are considered safe for deletion. The size of the bloom filter may impact its false positive rate, which can impact the results of offline pruning. This is an advanced parameter that has been tuned to 512 MB and should not be changed without thoughtful consideration.

offline-pruning-data-directory

String

This flag must be set when offline pruning is enabled and sets the directory that offline pruning will use to write its bloom filter to disk. This directory should not be changed in between runs until offline pruning has completed.

tx-lookup-limit (uint64)

Number of recent blocks for which to maintain transaction lookup indices in the database. If set to 0, transaction lookup indices will be maintained for all blocks. Defaults to 0.

skip-tx-indexing

Boolean

If set to true, the node will not index transactions. TxLookupLimit can be still used to control deleting old transaction indices. Defaults to false.

VM Networking

max-outbound-active-requests

Integer

Specifies the maximum number of outbound VM2VM requests in flight at once. Defaults to 16.

max-outbound-active-cross-chain-requests

Integer

Specifies the maximum number of outbound cross-chain requests in flight at once. Defaults to 64.

Miscellaneous

airdrop

String

Path to a json file that contains a list of addresses for a genesis airdrop. Each address will be airdropped AirdropAmount at genesis, and the hash of the airdrop file must match AirdropHash. AirdropAmount and AirdropHash are part of the genesis config. This option applies to subnet-evm only (not applicable to coreth).

skip-upgrade-check

Boolean

If set to true, the chain will skip verifying that all expected network upgrades have taken place before the last accepted block on startup. This allows node operators to recover if their node has accepted blocks after a network upgrade with a version of the code prior to the upgrade. Defaults to false.