Logging

Log files

Mina logs are stored in ~/.mina-config/:

File	Description	Size limit	Rotation
mina.log	Main daemon logs	10 MiB	50 files (mina.log.0 .. mina.log.50)
mina-best-tip.log	Best tip logs (useful for hard fork analysis)	5 MiB	1 file
mina-prover.log	Prover memory usage and batch sizes	128 MiB	1 file
mina-verifier.log	Verifier memory usage and batch sizes	128 MiB	1 file

Following logs

Depending on how you started the daemon:

# Docker
docker logs --follow mina-node

# Systemd
journalctl --user -u mina -n 1000 -f

# Direct
tail -f ~/.mina-config/mina.log

Log levels

The Mina daemon supports the following log levels, from most to least verbose:

1. Spam
2. Trace
3. Debug
4. Info (default for stdout)
5. Warn
6. Error
7. Fatal

Setting a level filters out all messages below it. For example, Info shows only Info, Warn, Error, and Fatal messages.

Log format

By default, logs are output as plain text. When -log-json is enabled, logs use the following JSON structure:

{
  "timestamp": "2020-12-23 21:25:04.616526Z",
  "level": "Error",
  "source": {
    "module": "Transition_router",
    "location": "File \"src/lib/transition_router/transition_router.ml\", line 231, characters 12-24"
  },
  "message": "Failed to find any peers during initialization (crashing because this is not a seed node)",
  "metadata": {
    "host": "1.1.1.2",
    "peer_id": "12D3KooWGQSPgo7ypy9717D3Vgz2RHaqB2ndDRHEFcAfJDAv284q",
    "pid": 12,
    "port": 8302
  }
}

Daemon logging options

Set these flags when starting the daemon:

Flag	Default	Description
-log-level	Info	Log level for stdout
-file-log-level	Trace	Log level for log files
-log-json	off	Output logs as JSON instead of plain text
-log-block-creation	true	Log steps for including transactions and SNARK work in a block
-log-received-blocks	false	Log blocks received from peers
-log-snark-work-gossip	false	Log snark-pool diffs received from peers
-log-txn-pool-gossip	false	Log transaction-pool diffs received from peers
-log-precomputed-blocks	false	Include precomputed blocks in logs

Exporting logs

From a running node

mina client export-logs -tarfile <FILENAME>

Compresses available logs into a .tar.gz archive in ~/.mina-config/exported_logs/. The -tarfile flag is optional and defaults to the current date-time.

Logs can also be exported via GraphQL using the exportLogs mutation.

From a stopped node

mina client export-local-logs -tarfile <FILENAME>

Same behavior, but works without a running daemon.

Crash reports

If the daemon crashes, it generates a crash report in ~/.mina-config/. Only the latest report is retained, named with the crash date-time.

A crash report may contain:

File	Description
crash_summary.json	System info, version, and final log output
mina_status.json	Output of mina client status at time of crash
mina_short.log	Last 4 MB of mina.log
registered_mask.dot	Latest ledger visualization
frontier.dot	Latest frontier visualization
daemon.json	Daemon configuration file

You can upload crash reports and exported logs directly to a GitHub issue to help with debugging.