Version: IOTA

# How to Run Hornet as a Verifier Node

A verifier node is a node which validates receipts. Receipts are an integral component of the migration mechanism used to migrate funds from the legacy network into the Chrysalis Phase 2 network. You can find a more detailed explanation on how the migration mechanism works in the Chrysalis documentation.

This guide explains how to configure a Hornet node as a verifier node:

1. Make sure you enabled the Receipts plugin under node.enablePlugins.
2. Set :
• receipts.validator.validate to true. This enables the verification logic in your node.
• receipts.validator.ignoreSoftErrors to true or false.
• Set it to true, if you don't want the verifier node to panic if it can not query a legacy node for data.
• Set it to false if you want to make sure that your verifier node panics if it can not query for data from a legacy node.
• An invalid receipt will always result in a panic. ignoreSoftErrors only controls API call failures to the legacy node.
• receipts.validator.api.timeout to something sensible like 10s (meaning 10 seconds).
• receipts.validator.api.address to the URI of your legacy node. Note that this legacy node must have the getWhiteFlagConfirmation and getNodeInfo API commands whitelisted.
• receipts.validator.coordinator.address to the Coordinator address in the legacy network.
• receipts.validator.coordinator.merkleTreeDepth to the correct used Merkle tree depth in the legacy network.
3. Run your Hornet verifier node and let it validate receipts.
note

We recommend that you use a load balanced endpoint to multiple legacy nodes for receipts.validator.api.address to obtain high availability.

After this, if your verifier node panics because of an invalid receipt, it is clear that one of the produced receipts is not valid. In this case, as a verifier node operator, you are invited to inform the community and the IOTA Foundation of your findings. This is, by the way, the same result as when the Coordinator issues a milestone, which diverges from a consistent ledger state.