change-ssh-port.sh

#!/bin/bash

# Run one of these following commands as root: 
# bash <(curl -Ls https://git.io/J9OER)
# bash <(curl -Ls https://gist.github.com/pcmehrdad/2fbc9651a6cff249f0576b784fdadef0/raw)

#RED="\e[31m"
#GREEN="\e[32m"
CLR_RED="\033[1;31m"
CLR_GREEN="\033[1;32m"
CLR_YELLOW="\033[1;33m"
CLR_BLUE="\033[1;34m"
CLR_PURPLE="\033[1;35m"
CLR_CYAN="\033[1;36m"
CLR_GREY="\033[0;37m"
CLR_RESET="\033[m"
CLR_END="\e[0m"

clear
if [[ $EUID != 0 ]]; then
	echo -e "Please run this as ${CLR_RED}root${CLR_END} user"
	exit 1
fi

echo -n -e "Please enter ${CLR_RED}new ssh port number${CLR_END} between 1024 and 65535 \n>"
while read SSHPORT; do
	if [[ "$SSHPORT" =~ ^[0-9]{2,5}$ || "$SSHPORT" = 22 ]]; then
		if [[ "$SSHPORT" -ge 1024 && "$SSHPORT" -le 65535 || "$SSHPORT" = 22 ]]; then
			# Backup current sshd config file
			# NOW_TIME=$(date +"%m_%d_%Y-%H_%M_%S")
			cp /etc/ssh/sshd_config /etc/ssh/sshd_config.inst.bckup.$(date +"%m_%d_%Y-%H_%M_%S")
			sed -i -e "/Port /c\Port $SSHPORT" /etc/ssh/sshd_config
			echo -e "Restarting SSH service. Please wait 5 seconds...\n"
			sleep 5
			service sshd restart
			echo ""
			echo -e "${CLR_GREEN}The SSH port has been changed to $SSHPORT ${CLR_END}.\n${CLR_YELLOW}Please login using that port to test BEFORE ending this session${CLR_END}.\n"
			exit 0
		else
			echo -e "${CLR_YELLOW}Invalid port${CLR_END}: It must be 22, or between 1024 and 65535."
			echo -n -e "Please enter ${CLR_RED}new ssh port number${CLR_END} between 1024 and 65535 \n>"
		fi
	else
		echo -e "${CLR_YELLOW}Invalid port${CLR_END}: Port number must be numeric!"
		echo -n -e "Please enter ${CLR_RED}new ssh port number${CLR_END} between 1024 and 65535 \n>"
	fi
done

echo ""

orginal script was here: