One-way Rsync mirror of data from source to destination. Run as a crontab.

mirror_mirror.sh

#!/usr/bin/env bash
#
# mirror_mirror
#
# One-way Rsync mirror of data from source to destination.
#
# Author: M. Krinitz <mjk235 [at] nyu [dot] edu>
# Date: 2020.04.20
# License: MIT
#
# Place script in, e.g.: /usr/local/sbin
# Set cronjob: sudo crontab -e, with, e.g.:
# 00 03 * * * /usr/local/sbin/mirror_mirror.sh 

############
# Variables 
############

LOG_DIRECTORY="/var/log"
LOG_FILE="rsync.log"

PORT_NUMBER="22"

TO="recipient@domain"
FROM="sender@domain"
SUBJECT="RSYNC_JOB_STATUS"
MAIL_CMD="mail --subject=$SUBJECT --return-address=$FROM --to $TO"

TIME_STAMP="$(date +"%b %d %X")"

SOURCE_DIRECTORY="/home/"

DESTINATION_USER="root"
DESTINATION_HOST="hostname.domain"
DESTINATION_DIRECTORY="/home"

RSYNC_EXCLUDE_LIST=".*"

RSYNC_CMD="
/usr/bin/rsync \
--archive \
--compress \
--delete \
--exclude="$RSYNC_EXCLUDE_LIST" \
--info=progress2 \
--log-file="$LOG_DIRECTORY/$LOG_FILE"
"
# For testing Rsync comment out the following: 
#--dry-run
#"

############
# Functions 
############

# Check if port on destination is open.
# Exit if port is closed & send e-mail notification.

port_check () {
  
  printf "%s\\n" "CHECKING PORT $PORT_NUMBER ON: $DESTINATION_HOST..."

  if ! nc -z $DESTINATION_HOST $PORT_NUMBER &>/dev/null; then
    printf "%s\\n" "ERROR: PORT $PORT_NUMBER NOT OPEN ON: $DESTINATION_HOST@$TIME_STAMP." \
    | $MAIL_CMD
    exit 1
  fi
}


# Check if Rsync lock file exists.
# Exit if lock files exists & send e-mail notification.

lock_file_check () {

  printf "%s\\n" "CHECKING FOR RSYNC LOCK FILE..."

  if [ -f /tmp/.rsync.lock ]; then
    printf "%s\\n" "ERROR: RSYNC LOCK FILE FOUND ON: $DESTINATION_HOST@$TIME_STAMP. TRY AGAIN LATER." \
    | $MAIL_CMD
    exit 1
  fi
}

# Make Rsync lock file.
# Exit if lock file can not be made & send e-mail notification.

make_lock_file () {

  /bin/touch /tmp/.rsync.lock

  if [ $? = "1" ]; then
    printf "%s\\n" "ERROR: COULD NOT CREATE RSYNC LOCK FILE ON: $DESTINATION_HOST@$TIME_STAMP." \
    | $MAIL_CMD 
    exit 1
  else
    printf "%s\\n" "RSYNC LOCK FILE CREATED..."
  fi
} 

# Run Rsync.

run_rsync () {

  printf "%s\\n" "STARTING RSYNC JOB..."

  nice --adjustment=20 \
  $RSYNC_CMD $SOURCE_DIRECTORY $DESTINATION_USER@$DESTINATION_HOST:$DESTINATION_DIRECTORY

  if [ $? = "1" ]; then
    printf "%s\\n" "ERROR: RSYNC FAILED DURING DATA TRANSFER ON: $DESTINATION_HOST@$TIME_STAMP." \
    | $MAIL_CMD
    exit 1
  else
    printf "%s\\n" "RSYNC COMPLETED SUCCESSFULLY ON: $DESTINATION_HOST@$TIME_STAMP." \
    "$LOG_FILE WRITTEN TO:$LOG_DIRECTORY." \
    | $MAIL_CMD
  fi
}

# Remove Rsync lock file.

remove_lock_file () {

  /bin/rm -rf /tmp/.rsync.lock

  printf "%s\\n" "REMOVING RSYNC LOCK FILE..."
  printf "%s\\n" "DONE! RSYNC COMPLETED SUCCESSFULLY @$TIME_STAMP. \
  $LOG_FILE WRITTEN TO: $LOG_DIRECTORY."
}

# Main function.

main () {
  port_check
  lock_file_check
  make_lock_file
  run_rsync
  remove_lock_file
} 

main "$@"