x/consensus

Functionality to modify CometBFT’s ABCI consensus params.

The x/consensus module allows governance to update CometBFT’s ABCI consensus parameters on a live chain without a software upgrade.

Consensus Parameters

The module manages the following CometBFT consensus parameters:

Block Parameters

Parameter	Description
MaxBytes	Maximum block size in bytes
MaxGas	Maximum gas per block (-1 for unlimited)

Evidence Parameters

Parameter	Description
MaxAgeNumBlocks	Maximum age of evidence in blocks
MaxAgeDuration	Maximum age of evidence as a duration
MaxBytes	Maximum total evidence size per block in bytes

Validator Parameters

Parameter	Description
PubKeyTypes	Supported public key types for validators (e.g., ed25519, secp256k1, bls12381)

ABCI Parameters

Parameter	Description
VoteExtensionsEnableHeight	Block height at which vote extensions are enabled (0 to disable)

Messages

MsgUpdateParams

Updates consensus parameters via governance. All of block, evidence, and validator must be provided. abci is optional.

msg := &types.MsgUpdateParams{
    Authority: authtypes.NewModuleAddress(govtypes.ModuleName).String(),
    Block: &cmtproto.BlockParams{
        MaxBytes: 200000,
        MaxGas:   100000000,
    },
    Evidence: &cmtproto.EvidenceParams{
        MaxAgeNumBlocks: 302400,
        MaxAgeDuration:  504 * time.Hour,
        MaxBytes:        10000,
    },
    Validator: &cmtproto.ValidatorParams{
        PubKeyTypes: []string{"ed25519"},
    },
    Abci: &cmtproto.ABCIParams{
        VoteExtensionsEnableHeight: 0,
    },
}

AuthorityParams

Authority management can be centralized via the x/consensus module using AuthorityParams. The AuthorityParams field in ConsensusParams stores the authority address on-chain. When set, it takes precedence over the per-keeper authority parameter.

Keeper constructors still accept the authority parameter. It is used as a fallback when no authority is configured in consensus params.

How It Works

When a module validates authority (e.g., in UpdateParams), it checks consensus params first. If no authority is set there, it falls back to the keeper’s authority field:

authority := sdkCtx.Authority() // from consensus params
if authority == "" {
    authority = k.authority       // fallback to keeper field
}
if authority != msg.Authority {
    return nil, errors.Wrapf(...)
}

To enable centralized authority, set the AuthorityParams in consensus params via a governance proposal targeting the x/consensus module’s MsgUpdateParams.

CLI

Query

params

Query the current consensus parameters:

simd query consensus params

Example Output:

params:
  abci:
    vote_extensions_enable_height: "0"
  block:
    max_bytes: "200000"
    max_gas: "-1"
  evidence:
    max_age_duration: 1814400s
    max_age_num_blocks: "302400"
    max_bytes: "10000"
  validator:
    pub_key_types:
    - ed25519

Transactions

update-params-proposal

Submit a governance proposal to update consensus parameters:

simd tx consensus update-params-proposal [block] [evidence] [validator] [abci] [flags]

Example:

simd tx consensus update-params-proposal \
  '{"max_bytes":"200000","max_gas":"100000000"}' \
  '{"max_age_num_blocks":"302400","max_age_duration":"1814400s","max_bytes":"10000"}' \
  '{"pub_key_types":["ed25519"]}' \
  '{"vote_extensions_enable_height":"0"}' \
  --from mykey

gRPC

Params

Query the current consensus parameters:

grpcurl -plaintext localhost:9090 cosmos.consensus.v1.Query/Params

Example Output:

{
  "params": {
    "block": {
      "maxBytes": "200000",
      "maxGas": "-1"
    },
    "evidence": {
      "maxAgeNumBlocks": "302400",
      "maxAgeDuration": "1814400s",
      "maxBytes": "10000"
    },
    "validator": {
      "pubKeyTypes": ["ed25519"]
    },
    "abci": {
      "voteExtensionsEnableHeight": "0"
    }
  }
}

REST

GET /cosmos/consensus/v1/params