Similar problem with output of "who" command too. rrm-leap15g:~ # who rashmi : 2018-04-18 10:28 (:) root : 2018-04-18 10:58 (:) rashmi tty2 2018-04-18 10:28 (tty2) root tty4 2018-04-18 10:58 (tty4) The above output is taken when two users (rashmi and root) are logged into desktops. Seems like both last and who commands are capturing two entries for each desktop login, but neither entries are capturing the display number properly.