↳ Backup & Restore of Smilo Nodes

Smilo supports export and import of chain data with built in tooling. This is an effective node backup mechanism adapted for the specific needs of Smilo such as private transactions, permissioning, and supported consensus algorithms.

!!! note Smilo chain data import and export must run after geth process is stopped.

↳ Node Backup (Export)

Backup functionality mimics original geth export command. Smilo export accepts 3 arguments:

1. Export file name required
2. First block
3. Last block are optional but must be provided together when used

↳ Sample command

geth export <export file name> --datadir <geth data dir>

↳ Node Restore (Import)

Restore functionality mimics original geth import command but requires transaction manager environment variable. Smilo import must run on a new node with an initialized --datadir after geth init has been executed. Restore supports arbitrary number of import files (at least 1).

!!! warning If private transactions are used in the chain data, Private Transaction Manager process for the original exported node must be running on the PTM ipc endpoint during import chain. Otherwise, nil pointer exceptions will be raised.

↳ Sample command

PRIVATE_CONFIG=<PTM ipc endpoint> geth import <import file names...> --datadir <geth data dir>

↳ Special Consensus Considerations

↳ IBFT

IBFT block data contains sealer information in the header, to restore a copy of exported chain data, the new node must be initialized use an IBFT genesis file with exact same validator set encoded in extra data field as original exported node's genesis.

↳ Raft

Raft backup do not account for current Raft state. An exported chain data from a Raft cluster can only be used by new nodes being added to that same cluster only.