Each umbrella app (indexer, explorer, block_scout_web, ethereum_json_rpc) contains a log rotation config in the prod.exs file.
Example: https://github.com/blockscout/blockscout/blob/master/apps/explorer/config/prod.exs#L36-L51
config :logger, :explorer,
  level: :info,
  path: Path.absname("logs/prod/explorer.log"),
  rotate: %{max_bytes: 52_428_800, keep: 19}

config :logger, :reading_token_functions,
  level: :debug,
  path: Path.absname("logs/prod/explorer/tokens/reading_functions.log"),
  metadata_filter: [fetcher: :token_functions],
  rotate: %{max_bytes: 52_428_800, keep: 19}
config :logger defines several variables including:
  • level: (info, debug, error) log level of detail
  • rotate: {max bytes: 52,428,800 max size in bytes for each file, keep: 19 max number of files to store}
If you are having issues with disc space, change the level, default number of files, and max bytes to consume less space with logs. Additional log rotation configs for ecto.log (DB interactions wrapper) and error.log are located in the common config file https://github.com/blockscout/blockscout/blob/master/config/config.exs#L47-L61