Nếu người dùng của bạn sử dụng bash, bạn có thể sử dụng tập lệnh /etc/bash.bash_logout để lưu một bản sao bổ sung của lịch sử ở định dạng được đóng dấu thời gian.
Ví dụ, tôi đã viết như sau để cung cấp bản kiểm tra xem ai đã làm gì và khi nào (trên một máy chủ có nhiều người dùng sudo) và cũng để lưu lại lịch sử trong trường hợp máy bị đột nhập:
#! /bin/bash
# /etc/bash.bash_logout
#
# Time-stamped bash history logging
# by Craig Sanders <cas@taz.net.au> 2008
#
# This script is public domain. Do whatever you want with it.
exec >& /dev/null
# LOGDIR must already exist and must be mode 1777 (same as /tmp)
# put it somewhere easily overlooked by script-kiddies. /var/log
# is a bad location because slightly-brighter-than-average SK's will
# often 'rm -rf /var/log' to cover their tracks.
LOGDIR='/var/tmp/.history'
[ -d "$LOGDIR" ] || exit 0
# Get current user name and who they logged in as.
CNAME=$(id -u -n)
LNAME=$(who am i | awk '{print $1}')
NAME="$LNAME--$CNAME"
# Get the TTY
TTY=$(tty)
# get the hostname and ip they logged in from
# short (non-fqdn) hostname:
RHOST_NAME=$(who -m | awk '{print $5}' | sed -r -e 's/[()]|\..*//g')
# or full hostname:
#RHOST_NAME=$(who -m | awk '{print $5}' | sed -r -e 's/[()]//g')
# if no RHOST_NAME, then login was on the console.
echo "$RHOST_NAME" | grep -q '[:/]' && RHOST_NAME="console"
# get the IP address
RHOST_IP=$(who -m --ips | awk '{print $5}')
echo "$RHOST_IP" | grep -q '[:/]' && RHOST_IP="console"
RHOST=$(echo "$RHOST_NAME--$RHOST_IP")
WHERE="$RHOST--$TTY"
WHERE=$(echo "$WHERE" | sed -e 's/\//-/g' -e 's/^-//')
# Filenames will be of the form:
# $LOGDIR/cas--root--localhost--127.0.0.1---dev-pts-1
# Ugly, but useful/informative. This example shows I logged in as cas
# from localhost, sudo-ed to root, and my tty was /dev/pts/1
HISTLOG="$LOGDIR/$NAME--$WHERE"
# Optionally rotate HISTLOG on each logout, otherwise new history
# sessions just get appended.
#[ -e "$HISTLOG" ] && savelog -l -c 21 -q $HISTLOG > /dev/null 2>&1
# Log some easily parseable info as a prelude, including the current
# history settings (an unusual HISTFILE or zero HISTSIZE setting is
# suspicious and worthy of investigation)
cat <<__EOF__ >> "$HISTLOG"
### TIME ### $(date +'%a,%Y-%m-%d,%H:%M:%S')
### FROM ### $RHOST_NAME,$RHOST_IP,$TTY
### USER ### $LNAME,$CNAME
### WHOM ### $(who -m)
### HIST ### $HISTFILE,$HISTSIZE
__EOF__
# Setting HISTTIMEFORMAT seems to be buggy. bash man page says it uses
# strftime, but all it seems to care about is whether it's set or not -
# 'history -a' always uses seconds since epoch, regardless of what it is
# set to.
HISTTIMEFORMAT="%s"
history -a "$HISTLOG"
# Now write history as normal (this seems buggy too. bash used to always
# write $HISTFILE anyway, but now it won't do it if you've already run
# 'history -a')
unset HISTTIMEFORMAT
history -w