Dynamic login messages with update-motd framework. Code for blog post https://fishi.devtail.io/weblog/2015/02/06/dyamic-login-messages-update-motd/

header.sh

# Simple static header for update-motd framework

COLOR_GREEN="\033[0;32m"
 
# print personal static banner in green
printf "${COLOR_GREEN}
  _____ .__         .__     .__ 
_/ ____\|__|  ______|  |__  |__|
\   __\ |  | /  ___/|  |  \ |  |
 |  |   |  | \___ \ |   Y  \|  |
 |__|   |__|/____  >|___|  /|__|
                 \/      \/     
 
Debian GNU/Linux 7.x\n\n" 

session-quote.sh

# Simple dynamic quote header for update-motd framework

COLOR_BLUE="\033[01;34m"
COLOR_DEFAULT="\033[0m"
 
# print a random session quote
printf "${COLOR_BLUE}Session Quote:\n" 
/usr/games/fortune 100% computers | /usr/games/cowsay -f tux
 
# reset color to terminal default
printf "${COLOR_DEFAULT}\n"

sys-info.sh

# Simple system performance counter retriever

# current date
date=`date`
 
# current cpu load
cpu_load=`cat /proc/loadavg | awk '{print $1*100 "%"}'`
 
# used memory
memory_usage=`free -m | awk '($1=="Mem:"){memTotal=$2} ($2=="buffers/cache:"){memUsed=$3} END{printf "%.1f%%", memUsed/memTotal * 100}'`
 
# used swap memory
swap_usage=`free -m | awk '($1=="Swap:"){swapTotal=$2; swapUsed=$3} END{printf "%.1f%%", swapUsed/swapTotal * 100}'`
 
# used disk space
disk_usage=`df -h | awk '{if($(NF) == "/") {print $(NF-1); exit;}}'`
 
# number of open user sessions
user_sessions=`users | wc -l`
 
# system uptime
sys_uptime=`uptime | awk '{print $3 " " $4}' | sed s'/.$//'`
 
# running processes
running_processes=`ps aux | wc -l`
 
# machine's IP address
used_ip=`ifconfig eth0 | grep "inet addr" | awk -F ":" '{print $2}' | awk '{print $1}'`

COLOR_DEFAULT="\033[0m"
COLOR_INFO="\033[0;37m"
COLOR_VALUE="\033[0;35m"
 
printf "${COLOR_INFO}System Information on ${date}\n"
printf "==================================================\n"
printf "${COLOR_INFO}CPU Usage         :${COLOR_VALUE} %s\n" "${cpu_load}"
printf "${COLOR_INFO}Memory Usage      :${COLOR_VALUE} %s\n" "${memory_usage}"
printf "${COLOR_INFO}Swap Usage        :${COLOR_VALUE} %s\n" "${swap_usage}"
printf "${COLOR_INFO}System Uptime     :${COLOR_VALUE} %s\n" "${sys_uptime}"
printf "${COLOR_INFO}IP Address        :${COLOR_VALUE} %s\n" "${used_ip}"
printf "${COLOR_INFO}Total Disk Usage  :${COLOR_VALUE} %s\n" "${disk_usage}" 
printf "${COLOR_INFO}Open Sessions     :${COLOR_VALUE} %s\n" "${user_sessions}" 
printf "${COLOR_INFO}Running Processes :${COLOR_VALUE} %s\n" "${running_processes}"
printf "${COLOR_DEFAULT}"