lnav(1)

LNAV(1) General Commands Manual LNAV(1)

NAME

lnav - log file viewer for the terminal

SYNOPSIS

lnav [options] [logfile1 logfile2 ...]

DESCRIPTION

The Logfile Navigator, lnav, is a log file viewer for the terminal. Given a set of files/directories, lnav will:

- decompress as needed;
- detect their format;
- merge the files together by time into a single view;
- tail the files, follow renames, find new files in directories;
- build an index of errors and warnings;
- pretty-print JSON-lines.

KEY BINDINGS

?
View/leave the online help text.
q
Quit the program.

OPTIONS

-h
Print help and exit
-H
Display the internal help text.
-I path
Add the given configuration directory to the search path.
-W
Print warnings related to lnav's configuration.
-u
Update formats installed from git repositories.
-d file
Write debug messages to the given file.
-V
Print version information.
-r
Recursively load files from the given directories.
-R
Load older rotated log files as well.
-c cmd
Execute a command after the files have been loaded.
-f path
Execute the commands in the given file.
-e cmd
Execute a shell command-line.
-t
Prepend timestamps to the lines of data being read in on the standard input.
-n
Run without the curses UI. (headless mode)
-N
Do not open the default syslog file if no files are given.
-q
Quiet mode. Do not print the log messages after executing all of the commands.

Optional arguments:

logfile1
The log files or directories to view. If a directory is given, all of the files in the directory will be loaded.

MANAGEMENT-MODE OPTIONS

-i
Install the given format files in the $HOME/.lnav/formats/installed directory and exit.
-m
Switch to the management command-line mode. This mode is used to work with lnav's configuration.
-C
Check the configuration and exit. The log format files will be loaded and checked. Any files given on the command-line will be loaded checked to make sure they match a log format.

EXAMPLES

To load and follow the syslog file:

    lnav

To load all of the files in /var/log:

    lnav /var/log

To watch the output of make with timestamps prepended:

    make 2>&1 | lnav -t

AUTHOR

This manual page was written by Salvatore Bonaccorso <carnil@debian.org> for the Debian system (but may be used by others).

April 2024