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"

TO="recipient@domain"
FROM="sender@domain"
SUBJECT="RSYNC_JOB_STATUS"
MAIL_CMD="mail -s \"$SUBJECT\" -r \"$FROM\" $TO"

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"
  --dry-run --itemize-changes
"
# --dry-run --itemize-changes
# allows you to test rsync without committing any changes

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

time_stamp() {
  date +"%b %d %X"
}

# 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
######

main() {
  lock_file_check
  make_lock_file
  run_rsync
  remove_lock_file
}

main "$@"