How to Log to Files with Log Rotation in Rust

Operations Observability
2026-04-17T14:12:14+00:00
TITLE: How to Log to Files with Log Rotation in Rust

TITLE: How to Log to Files with Log Rotation in Rust

Use the rotating_file_appender crate to handle file logging with automatic rotation based on size or time.

  1. Add the dependency to your Cargo.toml.
[dependencies]
rotating_file_appender = "2.2"
log = "0.4"
  1. Initialize the appender in src/main.rs and configure the logger.
use log::{info, LevelFilter};
use rotating_file_appender::{Builder, ConfigBuilder, rotating_file_appender};
use std::io;

fn main() -> io::Result<()> {
    let config = ConfigBuilder::default()
        .filename("app.log")
        .max_size(100_000_000) // 100MB
        .build();
    let appender = Builder::default()
        .config(config)
        .build()?;

    let logger = rotating_file_appender::Logger::new(appender);
    log::set_boxed_logger(Box::new(logger))
        .map(|()| log::set_max_level(LevelFilter::Info))
        .unwrap();

    info!("Application started");
    Ok(())
}
  1. Run your application to generate logs that rotate automatically.
cargo run