Chain ID

A chain ID is a unique identifier that represents a blockchain network. We use it to distinguish different blockchain networks from each other and to ensure that transactions and messages are sent to the correct network. Guru network follows the format of identifier_EIP155-version format.

tip

You can also look up the EIP-155 Chain ID by referring to chainlist.org.

The Chain Identifier

Every chain must have a unique identifier or chain-id. CometBFT requires each application to define its own chain-id in the genesis.json fields. However, to comply with both EIP-155 and Cosmos standard for chain upgrades, Guru-compatible chains must implement a special structure for their chain identifiers.

Structure

The Guru Chain ID contains 3 main components

• Identifier: Unstructured string that defines the name of the application.
• EIP-155 Number: Immutable EIP-155 CHAIN_ID that defines the replay attack protection number.
• Version Number: Is the version number (always positive) that the chain is currently running. This number MUST be incremented every time the chain is upgraded or forked to avoid network or consensus errors.

Format

The format for specifying and Guru compatible chain-id in genesis is the following:

{identifier}_{EIP155}-{version}

The following table provides an example where the second row corresponds to an upgrade from the first one:

ChainID	Identifier	EIP-155 Number	Version Number
guru_631-1	guru	631	1
guru_631-2	guru	631	2
...	...	...	...
guru_631-N	guru	631	N