huschi.net

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
       information in these files if they are present.  This is a  local  con-
       figuration  issue.   If you want the files to be used, they can be cre-
       ated with a simple touch(1) command (for example, touch /var/log/wtmp).
       The utmp file format uses fixed sizes of strings, which means that very
       long strings are impossible to store in the file and impossible to dis-
       play by last. The usual limits are 32 bytes for a user  and  line  name
       and 256 bytes for a hostname.
FILES
       /var/log/wtmp
       /var/log/btmp
AUTHOR
       Miquel van Smoorenburg <miquels AT 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)