LAST, LASTB(1) User Commands LAST, LASTB(1)
NAME
last, lastb - show a listing of last logged in users
SYNOPSIS
last [options] [username...] [tty...]
lastb [options] [username...] [tty...]
DESCRIPTION
last searches back through the /var/log/wtmp file (or the file desig-
nated by the -f option) and displays a list of all users logged in (and
out) since that file was created. One or more usernames and/or ttys
can be given, in which case last will show only the entries matching
those arguments. Names of ttys can be abbreviated, thus last 0 is the
same as last tty0.
When catching a SIGINT signal (generated by the interrupt key, usually
control-C) or a SIGQUIT signal, last will show how far it has searched
through the file; in the case of the SIGINT signal last will then ter-
minate.
The pseudo user reboot logs in each time the system is rebooted. Thus
last reboot will show a log of all the reboots since the log file was
created.
lastb is the same as last, except that by default it shows a log of the
/var/log/btmp file, which contains all the bad login attempts.
OPTIONS
-a, --hostlast
Display the hostname in the last column. Useful in combination
with the --dns option.
-d, --dns
For non-local logins, Linux stores not only the host name of the
remote host, but its IP number as well. This option translates
the IP number back into a hostname.
-f, --file file
Tell last to use a specific file instead of /var/log/wtmp. The
--file option can be given multiple times, and all of the speci-
fied files will be processed.
-F, --fulltimes
Print full login and logout times and dates.
-i, --ip
Like --dns , but displays the host's IP number instead of the
name.
-number
-n, --limit number
Tell last how many lines to show.
-p, --present time
Display the users who were present at the specified time. This
is like using the options --since and --until together with the
same time.
-R, --nohostname
Suppresses the display of the hostname field.
-s, --since time
Display the state of logins since the specified time. This is
useful, e.g., to easily determine who was logged in at a partic-
ular time. The option is often combined with --until.
-t, --until time
Display the state of logins until the specified time.
--time-format format
Define the output timestamp format to be one of notime, short,
full, or iso. The notime variant will not print any timestamps
at all, short is the default, and full is the same as the
--fulltimes option. The iso variant will display the timestamp
in ISO-8601 format. The ISO format contains timezone informa-
tion, making it preferable when printouts are investigated out-
side of the system.
-w, --fullnames
Display full user names and domain names in the output.
-x, --system
Display the system shutdown entries and run level changes.
TIME FORMATS
The options that take the time argument understand the following for-
mats:
YYYYMMDDhhmmss
YYYY-MM-DD hh:mm:ss
YYYY-MM-DD hh:mm (seconds will be set to 00)
YYYY-MM-DD (time will be set to 00:00:00)
hh:mm:ss (date will be set to today)
hh:mm (date will be set to today, seconds to 00)
now
yesterday (time is set to 00:00:00)
today (time is set to 00:00:00)
tomorrow (time is set to 00:00:00)
+5min
-5days
NOTES
The files wtmp and btmp might not be found. The system only logs in-
formation in these files if they are present. This is a local configu-
ration issue. If you want the files to be used, they can be created
with a simple touch(1) command (for example, touch /var/log/wtmp).
FILES
/var/log/wtmp
/var/log/btmp
AUTHOR
Miquel van Smoorenburg <miquels@cistron.nl>
AVAILABILITY
The last command is part of the util-linux package and is available
from Linux Kernel Archive <https://www.kernel.org/pub/linux/utils/util-
linux/>.
SEE ALSO
login(1), wtmp(5), init(8), shutdown(8)
util-linux October 2013 LAST, LASTB(1)