Bash terminal greeter

Wouldn't it be nice that every time you open up a terminal (or log in remotely), you would be greeted by a general overview of your system's health? Well, with this tool you can address this very problem.

This is a simple bash script that displays on top of new terminals a simple summary of your system's specs (useful if its a remote machine you just logged in) and a summary of your systems current load. Moreover, if the load is high, the color will change to draw your attention quickly, and when possible, will display what is causing the problem. Such as a report of CPU hungry processor an error report if a systemctl service has failed to load.

Source

---

You can find the latest iteration of this script in my GIT repository, among many other useful bash scripts; including this fancy bash prompt with triangles and colors.

To install it, simply copy the following text into your user's .bashrc file, or if you prefer to keep things tidy, paste it and source it with a new .bash_greeter.sh file by running this commands: 

nano ~/.bash_greeter.sh
echo "source ~/.bash_greeter.sh" >> ~/.bashrc

#!/bin/bash

##  +-----------------------------------+-----------------------------------+
##  |                                                                       |
##  |                    CLEAN BASH SYSTEM STATUS REPORT                    |
##  |                                                                       |
##  | Copyright (c) 2019, Andres Gongora <mail@andresgongora.com>.          |
##  |                                                                       |
##  | This program is free software: you can redistribute it and/or modify  |
##  | it under the terms of the GNU General Public License as published by  |
##  | the Free Software Foundation, either version 3 of the License, or     |
##  | (at your option) any later version.                                   |
##  |                                                                       |
##  | This program is distributed in the hope that it will be useful,       |
##  | but WITHOUT ANY WARRANTY; without even the implied warranty of        |
##  | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         |
##  | GNU General Public License for more details.                          |
##  |                                                                       |
##  | You should have received a copy of the GNU General Public License     |
##  | along with this program. If not, see <http://www.gnu.org/licenses/>.  |
##  |                                                                       |
##  +-----------------------------------------------------------------------+


##
## DESCRIPTION:
## This scripts prints to terminal a summary of your systems' status. This
## includes basic information about the OS and the CPU, as well as
## system resources, possible errors, and suspicions system activity.
##
##
## CUSTOMIZATION:
## Scroll down to the CUSTOMIZATION section to modify the logo and colors.
##
##
## INSTALLATION:
## Simply copy and paste this file into your ~/.bashrc file, or source
## it externally (recommended).
##
##
## TODO
##  Add a menu script that allows me to run some extra diagnostics, or
## by default (hitting enter), go into a simple terminal.
## Said options could include stuff like:
##  journalctl -p 3 -xb
##  netstat -atp #add -n to show IPs instead of host names
##  find -xtype l -print # Find broken symlinks
##  dmesg -TP --level=err,crit,alert,emerg
##
##
## SOURCES
## https://wiki.archlinux.org/index.php/System_maintenance
## https://unix.stackexchange.com/questions/125726/important-scripts-useful-for-a-linux-system-administrator
##


## =============================================================================
## COLOR DEFINITIONS
## =============================================================================

## REGULAR COLOROS
K='\033[0;30m' # black
R='\033[0;31m' # red
G='\033[0;32m' # green
Y='\033[0;33m' # yellow
B='\033[0;34m' # blue
M='\033[0;35m' # magenta
C='\033[0;36m' # cyan
W='\033[0;37m' # white
 
## BOLDFACE COLORS
BFK='\033[1;30m'
BFR='\033[1;31m'
BFG='\033[1;32m'
BFY='\033[1;33m'
BFB='\033[1;34m'
BFM='\033[1;35m'
BFC='\033[1;36m'
BFW='\033[1;37m'
BFO='\033[38;5;208m' # Orange bold
BFT='\033[38;5;118m' # Toxic green
 
## BACKGROUND COLORS
BGK='\033[40m'
BGR='\033[41m'
BGG='\033[42m'
BGY='\033[43m'
BGB='\033[44m'
BGM='\033[45m'
BGC='\033[46m'
BGW='\033[47m'

NC='\033[0m'  # NO COLOR



## =============================================================================
## CUSTOMIZATION
## =============================================================================

## COLORS
COLOR_INFO=${W} # INFO
COLOR_HL=${BFB} # HIGHLIGHT
COLOR_CRIT=${BFY} # CRITICAL
COLOR_DCO=${BFW} # DECORATION
COLOR_OK=${BFB} # OK STATUS
COLOR_ERR=${BFO} # ERROR
COLOR_LOGO=${BFB} # LOGO


## LOGOS
LOGO_01="${COLOR_LOGO}        -oydNMMMMNdyo-        ${NC}"
LOGO_02="${COLOR_LOGO}     -yNMMMMMMMMMMMMMMNy-     ${NC}"
LOGO_03="${COLOR_LOGO}   .hMMMMMMmhsooshmMMMMMMh.   ${NC}"
LOGO_04="${COLOR_LOGO}  :NMMMMmo.        .omMMMMN:  ${NC}"
LOGO_05="${COLOR_LOGO} -NMMMMs    -+ss+-    sMMMMN- ${NC}"
LOGO_06="${COLOR_LOGO} hMMMMs   -mMMMMMMm-   sMMMMh ${NC}"
LOGO_07="${COLOR_LOGO}'MMMMM.  'NMMMMMMMMN'  .MMMMM'${NC}"
LOGO_08="${COLOR_LOGO}'MMMMM.  'NMMMMMMMMN'   yMMMM'${NC}"
LOGO_09="${COLOR_LOGO} hMMMMs   -mMMMMMMMMy.   -yMh ${NC}"
LOGO_10="${COLOR_LOGO} -NMMMMs    -+ss+yMMMMy.   -. ${NC}"
LOGO_11="${COLOR_LOGO}  :NMMMMmo.       .yMMMMy.    ${NC}"
LOGO_12="${COLOR_LOGO}   .hMMMMMMmhsoo-   .yMMMy    ${NC}"
LOGO_13="${COLOR_LOGO}     -yNMMMMMMMMMy-   .o-     ${NC}"
LOGO_14="${COLOR_LOGO}        -oydNMMMMNd/          ${NC}"


## BEHAVIOUR
BAR_LENGTH=15
CRIT_CPU_PERCENT=50
CRIT_MEM_PERCENT=75
CRIT_SWAP_PERCENT=25
CRIT_HDD_PERCENT=80


## =============================================================================

##
## printBar(CURRENT, MAX, SIZE, CRIT_PERCENT)
##
## Prints a bar that is filled depending on the relation between
## CURRENT and MAX
##
## 1. CURRENT:     ammount to display on the bar.
## 2. MAX:         ammount that means that the bar should be printed
##                 completely full.
## 3. SIZE:        length of the bar as number of characters.
## 4. CRIT_PERCENT:between 0 and 100. Once the bar is over this percent, it
##   changes color.
##
printBar()
{
 CURRENT=$1
 MAX=$2
 SIZE=$3
 CRIT_PERCENT=$4


 ## COMPUTE VARIABLES
 NUM_BARS=$(($SIZE * $CURRENT / $MAX))
 CRIT_NUM_BARS=$(($SIZE * $CRIT_PERCENT / 100))
 BAR_COLOR=$COLOR_OK
 if [ $NUM_BARS -gt $CRIT_NUM_BARS ]; then
  BAR_COLOR=$COLOR_ERR
 fi
 
 ## PRINT BAR
 printf "${COLOR_DCO}[${BAR_COLOR}"
 i=0
 while [ $i -lt $NUM_BARS ]; do
  printf "|"
  i=$[$i+1]
 done
 while [ $i -lt $SIZE ]; do
  printf " "
  i=$[$i+1]
 done
 printf "${COLOR_DCO}]${NC}"


 ## PRINT BAR -> As background elements. Might be nicer... ????
 #printf "${BGW} "
 #i=0
 #while [ $i -lt $NUM_BARS ]; do
 # printf " "
 # i=$[$i+1]
 #done
 #printf "${NC}"
 #while [ $i -lt $SIZE ]; do
 # printf " "
 # i=$[$i+1]
 #done
 #printf "${NC}" 
}



printLastLogins()
{
 printf "${COLOR_HL}\nLAST LOGINS:\n${COLOR_INFO}"
 last -iwa | head -n 4 | grep -v "reboot"
}

## =============================================================================
## STATUS MESSAGES
## =============================================================================

## KERNEL INFO
KERNEL=$(uname -r)
KERNEL=$(echo -e "${COLOR_INFO}Kernel\t\t${COLOR_HL}$KERNEL${NC}")


## SHELL
SHELL=$(readlink /proc/$$/exe)
SHELL=$(echo -e "${COLOR_INFO}Shell\t\t${COLOR_HL}$SHELL${NC}")


## CPU INFO
CPU=$(cat /proc/cpuinfo | grep "model name" | uniq | cut -f1 -d "@")
CPU="${CPU#*:}"
CPU=$(echo "$CPU" | sed 's/  */ /g') # Trim spaces
CPU=$(echo -e "${COLOR_INFO}CPU\t\t${COLOR_HL}${CPU:1}${NC}")


## OS DISTRO NAME
OS=$(cat /etc/*-release | grep PRETTY_NAME)
OS="${OS#*=}"
OS=$(echo "$OS" | sed 's/"//g') # remove " characters
OS=$(echo -e "${COLOR_INFO}OS\t\t${COLOR_HL}$OS${NC}")


## SYS DATE
SYSDATE=$(date)
SYSDATE=$(echo -e "${COLOR_INFO}Date\t\t${COLOR_HL}$SYSDATE${NC}")


## LOGIN
LOGIN=$(echo -e "${COLOR_INFO}Login\t\t${COLOR_HL}$USER@$HOSTNAME${NC}")


## LOCAL IP
LOCALIP=$(ifconfig | sed -En 's/127.0.0.1//;s/.*inet (addr:)?(([0-9]*\.){3}[0-9]*).*/\2/p')
LOCALIP=$(echo -e "${COLOR_INFO}Local IP\t${COLOR_HL}$LOCALIP${NC}")


## EXTERNAL IP
EXTERNALIP=$(dig +short myip.opendns.com @resolver1.opendns.com)
EXTERNALIP=$(echo -e "${COLOR_INFO}External IP\t${COLOR_HL}$EXTERNALIP${NC}")


## SYSTEM CTL FAILED TO LOAD
NUM_FAILED=$(systemctl --failed | head -c 1)
if [ "$NUM_FAILED" -eq "0" ]; then
 SYSCTL=$(echo -e "${COLOR_INFO}SystemCTL\t${COLOR_HL}All services OK${NC}")
else
 SYSCTL=$(echo -e "${COLOR_INFO}SystemCTL\t${COLOR_ERR}$NUM_FAILED services failed!${NC}")
fi


PAD="   "

## CPU LOAD
CPU_AVG=$(cat /proc/loadavg | awk '{avg_1m=($1)} END {printf "%3.0f", avg_1m}')
CPU_MAX=$(cat /proc/cpuinfo | awk '/^processor/{print $3}' | wc -l)
CPU_BAR=$(printBar $CPU_AVG $CPU_MAX $BAR_LENGTH $CRIT_CPU_PERCENT)
CPU_PER=$(cat /proc/loadavg | awk '{printf "%3.0f\n",$1*100}')
CPU_PER=$(($CPU_PER / $CPU_MAX))
CPU_LOAD=$(echo -e "${COLOR_INFO}Sys load avg\t$CPU_BAR ${COLOR_HL}${CPU_PER:0:9} %%${NC}")


## MEMORY
MEM_INFO=$(free -m | head -n 2 | tail -n 1)
MEM_CURRENT=$(echo "$MEM_INFO" | awk '{mem=($2-$7)} END {printf "%4.0f", mem}')
MEM_MAX=$(echo "$MEM_INFO" | awk '{mem=($2)} END {printf "%1.0f", mem}')
MEM_BAR=$(printBar $MEM_CURRENT $MEM_MAX $BAR_LENGTH $CRIT_MEM_PERCENT)
MEM_MAX=$MEM_MAX$PAD
MEM_USAGE=$(echo -e "${COLOR_INFO}Memory\t\t$MEM_BAR ${COLOR_HL}$MEM_CURRENT${COLOR_INFO}/${COLOR_HL}${MEM_MAX:0:4} MB${NC}")


## SWAP
SWAP_INFO=$(free -m | tail -n 1)
SWAP_CURRENT=$(echo "$SWAP_INFO" | awk '{SWAP=($3)} END {printf "%4.0f", SWAP}')
SWAP_MAX=$(echo "$SWAP_INFO" | awk '{SWAP=($2)} END {printf "%1.0f", SWAP}')
SWAP_BAR=$(printBar $SWAP_CURRENT $SWAP_MAX $BAR_LENGTH $CRIT_SWAP_PERCENT)
SWAP_MAX=$SWAP_MAX$PAD
SWAP_USAGE=$(echo -e "${COLOR_INFO}Swap\t\t$SWAP_BAR ${COLOR_HL}$SWAP_CURRENT${COLOR_INFO}/${COLOR_HL}${SWAP_MAX:0:4} MB${NC}")


## HDD /
ROOT_CURRENT=$(df -BG / | grep "/" | awk '{key=($3)} END {printf "%4.0f", key}')
ROOT_MAX=$(df -BG "/" | grep "/" | awk '{key=($2)} END {printf "%1.0f", key}')
ROOT_BAR=$(printBar $ROOT_CURRENT $ROOT_MAX $BAR_LENGTH $CRIT_HDD_PERCENT)
ROOT_MAX=$ROOT_MAX$PAD
ROOT_USAGE=$(echo -e "${COLOR_INFO}Storage /\t$ROOT_BAR ${COLOR_HL}$ROOT_CURRENT${COLOR_INFO}/${COLOR_HL}${ROOT_MAX:0:4} GB${NC}")


## HDD /home
HOME_CURRENT=$(df -BG ~ | grep "/" | awk '{key=($3)} END {printf "%4.0f", key}')
HOME_MAX=$(df -BG ~ | grep "/" | awk '{key=($2)} END {printf "%1.0f", key}')
HOME_BAR=$(printBar $HOME_CURRENT $HOME_MAX $BAR_LENGTH $CRIT_HDD_PERCENT)
HOME_MAX=$HOME_MAX$PAD
HOME_USAGE=$(echo -e "${COLOR_INFO}Storage /home\t$HOME_BAR ${COLOR_HL}$HOME_CURRENT${COLOR_INFO}/${COLOR_HL}${HOME_MAX:0:4} GB${NC}")

## =============================================================================



WIDTH=$(tput cols)



printHeader()
{
 if [ "$WIDTH" -gt 90 ]; then
  printf "\n\r"
  printf "    $LOGO_01\t$OS  \n\r"
  printf "    $LOGO_02\t$KERNEL  \n\r"
  printf "    $LOGO_03\t$CPU  \n\r"
  printf "    $LOGO_04\t$SHELL  \n\r"
  printf "    $LOGO_05\t$SYSDATE  \n\r"
  printf "    $LOGO_06\t$LOGIN  \n\r"
  printf "    $LOGO_07\t$LOCALIP  \n\r"
  printf "    $LOGO_08\t$EXTERNALIP \n\r"
  printf "    $LOGO_09\t$SYSCTL  \n\r"
  printf "    $LOGO_10\t$CPU_LOAD  \n\r"
  printf "    $LOGO_11\t$MEM_USAGE \n\r"
  printf "    $LOGO_12\t$SWAP_USAGE \n\r"
  printf "    $LOGO_13\t$ROOT_USAGE \n\r"
  printf "    $LOGO_14\t$HOME_USAGE   \n\r\n\r"
 else
  printf "\n\r"
  printf " $LOGO_01  $OS  \n\r"
  printf " $LOGO_02  $KERNEL  \n\r"
  printf " $LOGO_03  $CPU  \n\r"
  printf " $LOGO_04  $SHELL  \n\r"
  printf " $LOGO_05  $SYSDATE  \n\r"
  printf " $LOGO_06  $LOGIN  \n\r"
  printf " $LOGO_07  $LOCALIP  \n\r"
  printf " $LOGO_08  $EXTERNALIP \n\r"
  printf " $LOGO_09  $SYSCTL  \n\r"
  printf " $LOGO_10  $CPU_LOAD  \n\r"
  printf " $LOGO_11  $MEM_USAGE \n\r"
  printf " $LOGO_12  $SWAP_USAGE \n\r"
  printf " $LOGO_13  $ROOT_USAGE \n\r"
  printf " $LOGO_14  $HOME_USAGE   \n\r\n\r"
 fi
}






printSystemctl()
{
 NUM_FAILED=$(systemctl --failed | head -c 1)
 if [ ! "$NUM_FAILED" -eq "0" ]; then
  printf "\n\r${COLOR_HL}SYSTEMCTL STATUS: ${COLOR_ERR}At least one service failed to load!!${NC}\n\r"
  systemctl --failed
 fi
}



printTop()
{
 if [ $CPU_PER -gt $CRIT_CPU_PERCENT ]; then
  TOP=$(top -b -d 5 -w 80| head -n 11)
  LOAD=$(echo "$TOP" | head -n 3 | tail -n 1)
  HEAD=$(echo "$TOP" | head -n 7 | tail -n 1)
  PROC=$(echo "$TOP" | tail -n 4 | grep -v "top")

  printf "\n\r${COLOR_HL}SYSTEM LOAD:${COLOR_INFO}  ${LOAD:8:35}${COLOR_HL}\n\r"
  echo "$HEAD"
  printf "${COLOR_INFO}$PROC${NC}"
 fi
}


## =============================================================================

clear
printHeader
#printLastLogins
printSystemctl
printTop


# EOF