Command line options

Command-line options

frontail [options] [file ...]

Any option can also be set in a configuration file. Command-line flags win over the file.

Server

Option	Default	Description
-h, --host <host>	0.0.0.0	Listening host
-p, --port <port>	9001	Listening port
--url-path <path>	/	URL path the app is served under (for reverse proxies)
-d, --daemonize		Run as a daemon
--pid-path <path>	/var/run/frontail.pid	Daemon PID file
--log-path <path>	/dev/null	Daemon log file
--config <path>		JSON configuration file
--metrics	off	Expose Prometheus metrics at <url-path>/metrics (details)

Sources

Option	Description
[file ...]	Files to tail; shell globs work. - reads stdin
-C, --container <container>	Docker/Podman container name or id (repeatable)
--container-engine <engine>	docker (default) or podman
--journal	Follow the systemd journal
--journal-unit <unit>	Follow one systemd unit (repeatable, implies --journal)
--ssh <target>	Follow a remote file: [user@]host:/absolute/path (repeatable)
-n, --number <number>	Lines to show on start (default 10)

Details and examples: Log sources.

Security

Option	Description
-U, --user <username>	Basic Auth user (also FRONTAIL_USER)
-P, --password <password>	Basic Auth password (also FRONTAIL_PASSWORD). Visible in ps; prefer --password-file
--password-file <path>	Read the password from a file, e.g. a Docker/Kubernetes secret
-k, --key <key.pem> / -c, --certificate <cert.pem>	Serve HTTPS (both required)
--allowed-origin <origin>	Extra browser origin allowed to open the log socket (repeatable)

Details: Security.

Web UI

Option	Description
-l, --lines <lines>	Lines kept in the browser (default 2000)
-t, --theme <theme>	default or dark start theme
--ui-hide-topbar	Hide the topbar
--ui-no-indent	Don't indent log lines
--ui-no-colors	Start with colorizing off (viewers can still toggle it)
--ui-colors-preset <path>	Extra colorizing rules: Custom format rules
--ui-highlight	Enable word/line highlighting
--ui-highlight-preset <path>	Custom highlight preset (see Web UI guide)

Other

Option	Description
-V, --version	Print the version
--help	Print usage
--disable-usage-stats	Deprecated no-op (usage statistics were removed)