146 lines
4.9 KiB
Groff
146 lines
4.9 KiB
Groff
'\" t
|
|
.\" Title: lastlog
|
|
.\" Author: Julianne Frances Haugh
|
|
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
|
|
.\" Date: 03/19/2025
|
|
.\" Manual: System Management Commands
|
|
.\" Source: shadow-utils 4.17.4
|
|
.\" Language: English
|
|
.\"
|
|
.TH "LASTLOG" "8" "03/19/2025" "shadow\-utils 4\&.17\&.4" "System Management Commands"
|
|
.\" -----------------------------------------------------------------
|
|
.\" * Define some portability stuff
|
|
.\" -----------------------------------------------------------------
|
|
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
.\" http://bugs.debian.org/507673
|
|
.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
|
|
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
.ie \n(.g .ds Aq \(aq
|
|
.el .ds Aq '
|
|
.\" -----------------------------------------------------------------
|
|
.\" * set default formatting
|
|
.\" -----------------------------------------------------------------
|
|
.\" disable hyphenation
|
|
.nh
|
|
.\" disable justification (adjust text to left margin only)
|
|
.ad l
|
|
.\" -----------------------------------------------------------------
|
|
.\" * MAIN CONTENT STARTS HERE *
|
|
.\" -----------------------------------------------------------------
|
|
.SH "NAME"
|
|
lastlog \- reports the most recent login of all users or of a given user
|
|
.SH "SYNOPSIS"
|
|
.HP \w'\fBlastlog\fR\ 'u
|
|
\fBlastlog\fR [\fIoptions\fR]
|
|
.SH "DESCRIPTION"
|
|
.PP
|
|
\fBlastlog\fR
|
|
formats and prints the contents of the last login log
|
|
/var/log/lastlog
|
|
file\&. The
|
|
\fIlogin\-name\fR,
|
|
\fIport\fR, and
|
|
\fIlast login time\fR
|
|
will be printed\&. The default (no flags) causes lastlog entries to be printed, sorted by their order in
|
|
/etc/passwd\&.
|
|
.SH "OPTIONS"
|
|
.PP
|
|
The options which apply to the
|
|
\fBlastlog\fR
|
|
command are:
|
|
.PP
|
|
\fB\-b\fR, \fB\-\-before\fR\ \&\fIDAYS\fR
|
|
.RS 4
|
|
Print only lastlog records older than
|
|
\fIDAYS\fR\&.
|
|
.RE
|
|
.PP
|
|
\fB\-C\fR, \fB\-\-clear\fR
|
|
.RS 4
|
|
Clear lastlog record of a user\&. This option can be used only together with
|
|
\fB\-u\fR
|
|
(\fB\-\-user\fR))\&.
|
|
.RE
|
|
.PP
|
|
\fB\-h\fR, \fB\-\-help\fR
|
|
.RS 4
|
|
Display help message and exit\&.
|
|
.RE
|
|
.PP
|
|
\fB\-R\fR, \fB\-\-root\fR\ \&\fICHROOT_DIR\fR
|
|
.RS 4
|
|
Apply changes in the
|
|
\fICHROOT_DIR\fR
|
|
directory and use the configuration files from the
|
|
\fICHROOT_DIR\fR
|
|
directory\&. Only absolute paths are supported\&.
|
|
.RE
|
|
.PP
|
|
\fB\-S\fR, \fB\-\-set\fR
|
|
.RS 4
|
|
Set lastlog record of a user to the current time\&. This option can be used only together with
|
|
\fB\-u\fR
|
|
(\fB\-\-user\fR))\&.
|
|
.RE
|
|
.PP
|
|
\fB\-t\fR, \fB\-\-time\fR\ \&\fIDAYS\fR
|
|
.RS 4
|
|
Print the lastlog records more recent than
|
|
\fIDAYS\fR\&.
|
|
.RE
|
|
.PP
|
|
\fB\-u\fR, \fB\-\-user\fR\ \&\fILOGIN\fR|\fIRANGE\fR
|
|
.RS 4
|
|
Print the lastlog record of the specified user(s)\&.
|
|
.sp
|
|
The users can be specified by a login name, a numerical user ID, or a
|
|
\fIRANGE\fR
|
|
of users\&. This
|
|
\fIRANGE\fR
|
|
of users can be specified with a min and max values (\fIUID_MIN\-UID_MAX\fR), a max value (\fI\-UID_MAX\fR), or a min value (\fIUID_MIN\-\fR)\&.
|
|
.RE
|
|
.PP
|
|
\fB\-a\fR
|
|
.RS 4
|
|
Print the lastlog records of the users that have logged in at least once\&. Excludes records for users with \*(Aq**Never logged in**\*(Aq\&.
|
|
.RE
|
|
.PP
|
|
If the user has never logged in the message
|
|
\fI** Never logged in**\fR
|
|
will be displayed instead of the port and time\&.
|
|
.PP
|
|
Only the entries for the current users of the system will be displayed\&. Other entries may exist for users that were deleted previously\&.
|
|
.SH "NOTE"
|
|
.PP
|
|
The
|
|
lastlog
|
|
file is a database which contains info on the last login of each user\&. You should not rotate it\&. It is a sparse file, so its size on the disk is usually much smaller than the one shown by "\fBls \-l\fR" (which can indicate a really big file if you have in
|
|
passwd
|
|
users with a high UID)\&. You can display its real size with "\fBls \-s\fR"\&.
|
|
.SH "CONFIGURATION"
|
|
.PP
|
|
The following configuration variables in
|
|
/etc/login\&.defs
|
|
change the behavior of this tool:
|
|
.PP
|
|
\fBLASTLOG_UID_MAX\fR (number)
|
|
.RS 4
|
|
Highest user ID number for which the lastlog entries should be updated\&. As higher user IDs are usually tracked by remote user identity and authentication services there is no need to create a huge sparse lastlog file for them\&.
|
|
.sp
|
|
No
|
|
\fBLASTLOG_UID_MAX\fR
|
|
option present in the configuration means that there is no user ID limit for writing lastlog entries\&.
|
|
.RE
|
|
.SH "FILES"
|
|
.PP
|
|
/var/log/lastlog
|
|
.RS 4
|
|
Database times of previous user logins\&.
|
|
.RE
|
|
.SH "CAVEATS"
|
|
.PP
|
|
Large gaps in UID numbers will cause the lastlog program to run longer with no output to the screen (i\&.e\&. if in lastlog database there is no entries for users with UID between 170 and 800 lastlog will appear to hang as it processes entries with UIDs 171\-799)\&.
|
|
.PP
|
|
Having high UIDs can create problems when handling the
|
|
/var/log/lastlog
|
|
with external tools\&. Although the actual file is sparse and does not use too much space, certain applications are not designed to identify sparse files by default and may require a specific option to handle them\&.
|